fix(edit-history): review round 3 — restored sessions read again, /clear reads the old conversation to its end, bounded memory

- remove() drops the session's slot once the file is gone: a session that comes
  back with the same id (reboot restore) starts afresh instead of answering
  `removed` until the next restart. A run in flight stays on its own slot's store,
  and the routes start a sync in the same tick as their session check, so a
  deletion right after it still stops that sync. A store that is not loaded is
  deleted without being parsed (deleteStore).
- A new conversation (/clear, resume) first reads the previous transcript, next
  to the new one, to its end with its subagents, so edits it got after the last
  read are not lost with its cursors. "Load older" reads the stored conversation
  while the switch is pending.
- At most MAX_LOADED_STORES (3) stores stay in memory; the least recently used one
  without a run is written if it changed (settle) and loads again on demand.
- Tmp files are named per process start, so a reused pid (a container's pid 1)
  no longer keeps a stale one through the startup sweep.
- load() keeps only a plain transcript id (the previous transcript's path is built
  from it) and no cursors without one; a pending Bash call with an id, cwd or
  agent id over 4,096 characters is not kept at parse time either.
- nextRange() is gone: production reads forward through the reader. The store
  tests mirror the reader's range choice, and a new end-to-end test runs the
  real reader, sync and store (/clear cases, 40 seeded random transcripts).
- The wiring guard scans all of src for holders of the sync.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/api-reference.md

@@ -1087,11 +1087,11 @@ Lists are capped (300 files and 50 commits per repository) while the counts stay
 
 What the Edit history panel reads (Settings → Header & Panels → Header, per-device, default off): the edits a **local claude session** made, main agent and subagents, read from its transcripts. Read-only. Every route resolves the session through `findSessionOrFail` (another user's session is `404`). Remote, Docker and non-claude sessions answer `state: 'unsupported'` and are never read.
 
-`GET /api/sessions/:id/edits[?sync=1]` lists the stored edits, newest first, without diffs: `{ state, reason?, backfillTruncated, agents, entries }`. With `sync=1` it first reads what the transcripts gained since the last read; without it the server reads nothing. `state` is `ok`, `unavailable` (stored entries only; `reason` is `no-transcript` before the session has a transcript Codeman can find, `removed` once the session's history was deleted, or the read error; the transcript is the one the session's hooks report, else the newest `<id>.jsonl` under the session's `CLAUDE_CONFIG_DIR` override or the server's config dir) or `unsupported` (`reason`: `remote`, `docker`, `mode`). Each entry is `{ id, ts, path, relPath, kind: 'code'|'image', tool, created, added, removed, truncated, agentId? }`, where `tool` is the edit tool, `bash` for an image a Bash call produced or `sent` for one the agent sent; `relPath` is relative to the workspace (a subagent's worktree for its edits). `agents` maps a subagent id to `{ description, agentType, worktreeBranch? }`. `backfillTruncated: true` means older edits can still be loaded.
+`GET /api/sessions/:id/edits[?sync=1]` lists the stored edits, newest first, without diffs: `{ state, reason?, backfillTruncated, agents, entries }`. With `sync=1` it first reads what the transcripts gained since the last read (after `/clear` or a resume, the previous conversation's transcripts to their end first); without it the server reads nothing. `state` is `ok`, `unavailable` (stored entries only; `reason` is `no-transcript` before the session has a transcript Codeman can find, `removed` while the session's history is being deleted, or the read error; the transcript is the one the session's hooks report, else the newest `<id>.jsonl` under the session's `CLAUDE_CONFIG_DIR` override or the server's config dir) or `unsupported` (`reason`: `remote`, `docker`, `mode`). Each entry is `{ id, ts, path, relPath, kind: 'code'|'image', tool, created, added, removed, truncated, agentId? }`, where `tool` is the edit tool, `bash` for an image a Bash call produced or `sent` for one the agent sent; `relPath` is relative to the workspace (a subagent's worktree for its edits). `agents` maps a subagent id to `{ description, agentType, worktreeBranch? }`. `backfillTruncated: true` means older edits can still be loaded.
 
 `GET /api/sessions/:id/edits/:entryId` returns one edit's diff as unified text: `{ diff, truncated }` (each edit's diff is capped at 64 KiB). `404` for an edit the session does not have.
 
-`POST /api/sessions/:id/edits/older` reads the next older block of up to three transcripts, a full read budget each (with more transcripts, main and subagents take turns), and answers like the list.
+`POST /api/sessions/:id/edits/older` reads the next older block, within the current conversation, of up to three transcripts, a full read budget each (with more transcripts, main and subagents take turns), and answers like the list.
 
 The edits are stored per session in `~/.codeman/edit-history/<id>.json` (mode 0600, at most 500 edits and 4 MiB of diff text, the oldest dropped), deleted when the session's record is removed (a killed pinned session keeps it; at startup, a file whose session no longer exists is deleted too) and never fed into `/api/v1/search`. No route here serves a file: the panel shows thumbnails through `file-raw` inside the workspace only; an image outside it opens in the file preview, which registers it through the attachment route.
 

docs/architecture-invariants.md

@@ -728,11 +728,11 @@ Matching semantics: a query containing `/` matches the relative path, otherwise
 
 ⚠️ **Reads only on request, opt-in all the way down.** `server.ts` builds the `EditHistorySync` and hands it to the routes; its only own calls are `remove` (through `forgetEditHistory`, when the session's persisted record goes), `sweep` (startup) and `flushAll` (shutdown). No hook, no timer, no second watcher. The panel drives every read: `?sync=1` when it opens, and while it is open on that session a debounced (600 ms) re-read after a `transcript:tool_end` of an edit-capable tool (Edit, Write, MultiEdit, NotebookEdit, Bash, Agent, Task, SendUserFile), which the existing `TranscriptWatcher` already broadcasts, or the session's `session:idle` (the end of a turn, via `_onSessionIdle`; it also catches a background subagent that writes after the tool end that started it). Not `transcript:complete`: it fires on a `result` line, which claude's interactive transcript never has. A closed panel reads nothing and keeps no badge. Guarded by the "reads only on request" wiring test in `test/edit-history-sync.test.ts`.
 
-⚠️ **Which transcript** (`resolveClaudeTranscript`). The main transcript is the path the session's `TranscriptWatcher` follows (the hook-reported `transcript_path`), so a session is read from where its claude really writes, whatever its `CLAUDE_CONFIG_DIR`. Without a watcher (server restarted, no hook since), `findClaudeTranscript()` looks for `<claudeSessionId|id>.jsonl` under `claudeProjectsDir(session.claudeConfigDir())`: the session's own override (#255, the same dir the relaunch pin checks), else the server's. A config dir set outside Codeman (a shell profile, a wrapper) is never guessed: until the next hook such a session answers `unavailable` / `no-transcript`, and the panel says so. Subagents are `<main path without .jsonl>/subagents/agent-<id>.jsonl`. A different main file (`/clear`, resume) is read from its end with fresh cursors; the stored entries stay.
+⚠️ **Which transcript** (`resolveClaudeTranscript`). The main transcript is the path the session's `TranscriptWatcher` follows (the hook-reported `transcript_path`), so a session is read from where its claude really writes, whatever its `CLAUDE_CONFIG_DIR`. Without a watcher (server restarted, no hook since), `findClaudeTranscript()` looks for `<claudeSessionId|id>.jsonl` under `claudeProjectsDir(session.claudeConfigDir())`: the session's own override (#255, the same dir the relaunch pin checks), else the server's. A config dir set outside Codeman (a shell profile, a wrapper) is never guessed: until the next hook such a session answers `unavailable` / `no-transcript`, and the panel says so. Subagents are `<main path without .jsonl>/subagents/agent-<id>.jsonl`. A different main file (`/clear`, resume): the previous one, next to it in the same directory, is first read to its end with its subagents (over as many syncs as that takes), then the new one from its end with fresh cursors; the stored entries stay. "Load older" reaches back within the current conversation only, and reads the stored conversation's transcript while the switch is still pending.
 
-⚠️ **Bounded reads.** A sync is at most `MAX_FORWARD_PASSES` (3) reads, each at most `READ_BUDGET_BYTES` (8 MiB) shared by the main transcript and all subagents (main first); a first read starts that far before the end. A file whose chunk the shared budget cut short is not applied but read in a later pass (the store would take a chunk with no line end for one line longer than the budget). "Load older" reads a full-budget block of up to `MAX_OLDER_SOURCES` (3) transcripts per click; with more, they take turns. A line longer than the budget is skipped, going forward and going back, and the line after (before) it is read whole. A subagent transcript that vanished loses its cursor, not its entries. Parsing happens in the request, line by line; nothing runs on the PTY data path. One sync per session at a time, and requests during a run fold into one more run.
+⚠️ **Bounded reads.** A sync is at most `MAX_FORWARD_PASSES` (3) reads, each at most `READ_BUDGET_BYTES` (8 MiB) shared by the main transcript and all subagents (main first), plus up to 8 KiB of `meta.json` per subagent seen for the first time; a first read starts that far before the end. A file whose chunk the shared budget cut short is not applied but read in a later pass (the store would take a chunk with no line end for one line longer than the budget). "Load older" reads a full-budget block of up to `MAX_OLDER_SOURCES` (3) transcripts per click; with more, they take turns. A line longer than the budget is skipped, going forward and going back, and the line after (before) it is read whole. A subagent transcript that vanished loses its cursor, not its entries. Parsing happens in the request, line by line; nothing runs on the PTY data path. One sync per session at a time, and requests during a run fold into one more run. At most `MAX_LOADED_STORES` (3) stores stay in memory: past that the least recently used one without a run in flight is written (only if it changed) and dropped, and a later request loads it again after that write.
 
-⚠️ **The store holds secrets.** Every diff an agent wrote ends up in `dataPath('edit-history')/<sessionId>.json`, API keys and `.env` contents included. It is written 0600 via tmp + rename (a fresh file each time, so an existing store never keeps wider bits; a new directory is created 0700) and bounded per session: `MAX_ENTRIES` (500) and `MAX_STORE_BYTES` (4 MiB of diff text, paths and ids), oldest dropped, also on load. Each edit's diff is capped at `MAX_HUNK_BYTES` (64 KiB); the file also holds at most `MAX_PENDING_BASH` (200) unanswered Bash calls of at most 8,192 characters of command text each and `MAX_AGENTS` (501) subagent labels of at most 1,024 characters per string. `load()` takes the file as untrusted: one over `MAX_FILE_BYTES` (32 MiB) is not parsed, and the rest is rebuilt from its known fields under the same bounds (unknown fields and non-string diff lines dropped, the per-edit cap applied again). Writes are serialized. The store lives as long as the session's persisted record: `forgetEditHistory` runs when `cleanupSession` with `killMux` removes the record (a pinned session's record is only demoted and keeps its history), on the persisted-only `DELETE /api/sessions/:id`, for every record `cleanupStaleSessions` drops at startup and every one `POST /api/cleanup-state` drops. After that startup cleanup, `sweep` deletes the `edit-history/*.json` files whose session is neither live nor recorded (left behind by a crash between removing the record and deleting the file, or by an older build) and tmp files of other processes. After `remove()` nothing writes the file again, neither a sync in flight nor a later request (the session answers `unavailable` / `removed`). The store is blocked in `isSensitivePath` (`/.codeman*/edit-history/`, same reasoning as `intents.json`) and never fed to `/api/search`.
+⚠️ **The store holds secrets.** Every diff an agent wrote ends up in `dataPath('edit-history')/<sessionId>.json`, API keys and `.env` contents included. It is written 0600 via tmp + rename (a fresh file each time, so an existing store never keeps wider bits; a new directory is created 0700) and bounded per session: `MAX_ENTRIES` (500) and `MAX_STORE_BYTES` (4 MiB of diff text, paths and ids), oldest dropped, also on load. Each edit's diff is capped at `MAX_HUNK_BYTES` (64 KiB); the file also holds one cursor per transcript file of the current conversation, at most `MAX_PENDING_BASH` (200) unanswered Bash calls of at most 8,192 characters of command text each (a call with an id, cwd or agent id over 4,096 characters is not kept, and dropped on load) and `MAX_AGENTS` (501) subagent labels of at most 1,024 characters per string. `load()` takes the file as untrusted: one over `MAX_FILE_BYTES` (32 MiB) is not parsed, and the rest is rebuilt from its known fields under the same bounds (unknown fields and non-string diff lines dropped, the per-edit cap applied again, a transcript id with anything but `[A-Za-z0-9._-]` dropped, since the previous transcript's path is built from it). Writes are serialized. The store lives as long as the session's persisted record: `forgetEditHistory` runs when `cleanupSession` with `killMux` removes the record (a pinned session's record is only demoted and keeps its history), on the persisted-only `DELETE /api/sessions/:id`, for every record `cleanupStaleSessions` drops at startup and every one `POST /api/cleanup-state` drops. After that startup cleanup, `sweep` deletes the `edit-history/*.json` files whose session is neither live nor recorded (left behind by a crash between removing the record and deleting the file, or by an older build) and tmp files of earlier runs (named per process start, so a pid used again, a container's pid 1, does not keep one). While `remove()` runs, nothing writes the file again: a sync in flight stops after its current read, and a request meanwhile reads nothing (`unavailable` / `removed`). The routes start a sync in the same tick as their session check, so a request that passed the check before the deletion cannot start one afterwards. Then the session's slot goes, and a session that comes back with the same id (reboot restore re-creates it) starts afresh. A store that is not loaded is deleted without being parsed. The store is blocked in `isSensitivePath` (`/.codeman*/edit-history/`, same reasoning as `intents.json`) and never fed to `/api/search`.
 
 ⚠️ **Images only through existing file surfaces.** A Bash image candidate counts only when the file's mtime lies in the call's window (start − 2 s … end + 2 s) and no entry already covers that file version; `SendUserFile` images need no window. The panel shows a thumbnail only inside the workspace, through the confined `file-raw` route. An image outside it gets no thumbnail (each would mint an attachment id per render); a click opens the shared file preview, which registers it once through `POST /api/sessions/:id/attachments` with `notify: false` (its extension allowlist and `isSensitivePath` apply). SVGs get no thumbnail. No route of this feature serves a file, least of all a transcript path.
 

docs/wiki/Working-With-Files.md

@@ -275,6 +275,9 @@ Click it for a draggable window listing the active session's edits, newest first
   to open it in the preview.
 - **Load older** reads further back in the conversation, in the main agent's transcript and the
   subagents' alike (up to three transcripts per click; with more, they take turns).
+- After `/clear` or a resume, the edits of the earlier conversation stay listed, and the window
+  first catches up on the ones it had not read yet. **Load older** then goes back within the new
+  conversation.
 
 It works for local Claude sessions only. Remote (SSH), Docker and other CLIs' sessions say so instead.