feat(mobile): phone Attach button and camera-roll video uploads

A phone-only toolbar Attach button hands the agent a photo or a video with the
keyboard down. It owns its own file input, positioned over the button so iOS
anchors the picker popover to it; the picked paths land on the prompt as unsent
text, so Compose adopts them together with anything already typed and Use
terminal keyboard hands a single-line draft back the other way.

Videos take a second path on the same route: ?kind=video streams the file to
disk under MAX_PASTE_VIDEO_BYTES (1GB, env CODEMAN_MAX_PASTE_VIDEO_BYTES)
instead of buffering it, sniffs the container from the first bytes as they
arrive, drains a mislabeled body unwritten and unlinks on any failure. It draws
on its own 3/min per-(IP, session) rate bucket beside the image path's 30/min:
at 1GB each, 30/min would be 30GB of disk a minute. Without the flag the route
is byte-identical to the image-only version, same 50MB cap and same bucket.

One client classifier, _promptAttachKind (MIME first, then the name's
extension), drives every pick and paste surface: the Attach button, terminal
drop, the tile grid's drop, the Compose and paste-dialog pickers and the
clipboard handlers. A pick that lands while the tile grid owns the terminal
goes to the PTY rather than the parked main-terminal overlay.

CLAUDE.md

@@ -297,7 +297,7 @@ Codeman is a Claude Code session manager with web interface and autonomous Ralph
 
 **Attachments** (live external document references; all wiring in `file-routes.ts`): a **registry** maps a stable `attachmentId` to a realpath-resolved, extension-allowlisted absolute path, so browser requests never carry arbitrary absolute paths. ⚠️ The **magic-link scanner** (`codeman://attach?...` in terminal output) is **prompt-injectable**, so its scan path is force-confined to the session workspace; a hostile prompt could otherwise exfiltrate arbitrary host files over SSE. The security gate is an extension **allowlist**, not a blocklist. `document-conversion-limiter.ts` caps converter spawns globally: without it, N large docs detected at once fork N multi-minute processes, which is a resource-exhaustion vector. → [architecture-invariants#attachments](docs/architecture-invariants.md#attachments)
 
-**Prompt uploads** (`POST /api/sessions/:id/paste-image`; client wiring in `image-input.js` and `keyboard-accessory.js`): a pasted file is written to `<workspace>/.codeman-uploads/` and its path lands on the prompt as unsent text. The folder is IN the workspace because that is the only path identical for a local and a container agent, FLAT because `<workspace>/.codeman/` would BE the data dir when the workspace is the home directory, and self-ignoring through a `.gitignore` of `*` written ONCE with `wx` (a file already there is the user's and is never overwritten; the user's own ignore file is never touched). ⚠️ The directory names live ONLY in `paste-image-gc.ts` (`UPLOAD_DIR_NAMES`): the pre-move `.claude-images/` receives nothing but stays readable for one release, so the GC sweep and the delete cleanup (through `uploadDirs()`) and the image watcher's ignore filter (reading the names) cover BOTH; retire the legacy entry there, never by hand elsewhere. ⚠️ `uploadDirs()` is async and probes the workspace BOUNDED first (`probePathKind()`, the #516 rule: an `unknown` path is skipped, never touched; the sweep keeps the stall cap and the delete passes `pastCap`), then returns only REAL directories (lstat, so a planted symlink is never one), none that is or contains `getDataDir()` (one strictly inside it only holds uploads and is listed), and none for a remote session, since both consumers delete; the check is made at list time, and the same-user race after it is accepted. A remote (SSH) session is refused (400) before any disk touch: its `workingDir` is the remote path, so the file would land on THIS host where the agent cannot read it. → [architecture-invariants#buffers-uploads-and-terminal-history](docs/architecture-invariants.md#buffers-uploads-and-terminal-history)
+**Prompt uploads** (`POST /api/sessions/:id/paste-image`: clipboard paste, drop, the Compose Attach key and the phone toolbar's Attach button; client wiring in `image-input.js` and `keyboard-accessory.js`): a pick is written to `<workspace>/.codeman-uploads/` and its path lands on the prompt as unsent text. The folder is IN the workspace because that is the only path identical for a local and a container agent, FLAT because `<workspace>/.codeman/` would BE the data dir when the workspace is the home directory, and self-ignoring through a `.gitignore` of `*` written ONCE with `wx` (a file already there is the user's and is never overwritten; the user's own ignore file is never touched). ⚠️ The directory names live ONLY in `paste-image-gc.ts` (`UPLOAD_DIR_NAMES`): the pre-move `.claude-images/` receives nothing but stays readable for one release, so the GC sweep and the delete cleanup (through `uploadDirs()`) and the image watcher's ignore filter (reading the names) cover BOTH; retire the legacy entry there, never by hand elsewhere. ⚠️ `uploadDirs()` is async and probes the workspace BOUNDED first (`probePathKind()`, the #516 rule: an `unknown` path is skipped, never touched; the sweep keeps the stall cap and the delete passes `pastCap`), then returns only REAL directories (lstat, so a planted symlink is never one), none that is or contains `getDataDir()` (one strictly inside it only holds uploads and is listed), and none for a remote session, since both consumers delete; the check is made at list time, and the same-user race after it is accepted. Images are buffered in memory under `MAX_PASTE_IMAGE_BYTES` (50MB) after a client-side canvas re-encode. A VIDEO is never buffered: `?kind=video` streams it to disk under `MAX_PASTE_VIDEO_BYTES` (1GB, env `CODEMAN_MAX_PASTE_VIDEO_BYTES`), judges the container on the first 12 bytes as they arrive (ISO BMFF / QuickTime atom, EBML for webm, Ogg for ogv; a mislabeled body is drained unwritten from there, never parked on disk first) and unlinks on any failure, a dead transfer included. ⚠️ The flag is the ONLY way onto that path and admits video types alone (the registry's `VIDEO_ATTACHMENT_EXTENSIONS`, single-sourced: mp4/webm/mov/m4v/ogv, so an uploaded video is one the file viewer can also play; 3gp/mkv are out, since a phone's camera roll produces neither and neither previews), so an image can never ride the larger cap through memory; without it the route is byte-identical to the image-only version. Busboy takes its size limit before the part is seen, which is why the choice rides the URL and not the file. ⚠️ A video draws on its OWN per-(IP, session) rate bucket (`consumeVideoToken`, 3/min) beside the image bucket (`consumePasteToken`, 30/min): at 1GB each, 30/min would be 30GB of disk a minute, so the lower rate bounds it to 3GB; the image path keeps the 30/min bucket and is unchanged without the flag. A remote (SSH) session is refused (400) before any disk touch: its `workingDir` is the remote path, so the file would land on THIS host where the agent cannot read it (Docker is fine, the workspace is bind-mounted at the same absolute path). ⚠️ The client classifies a pick through ONE helper, `_promptAttachKind()` (MIME type first, then the name's extension, because some Android file managers hand over a File with none); every pick and paste filter (Attach, drop, the tile grid's drop in `tile-grid.js`, the Compose and paste-dialog pickers, the clipboard handlers), the flag and the re-encode gate read it, never `file.type` directly. ⚠️ A pick that lands while the tile grid owns the terminal goes to the PTY, never the main terminal's overlay: that terminal is parked and hidden then, and a tile's Enter cannot flush it (`_tilesOwnTerminal()` in the `_attachFromToolbar` guard). Tests: `test/toolbar-attach.test.ts`, `test/mobile-prompt-composer.test.ts`, `test/paste-image-gc.test.ts`, `test/paste-image-dir-shared.test.ts`, the paste-image block of `test/routes/session-routes.test.ts`. → [architecture-invariants#buffers-uploads-and-terminal-history](docs/architecture-invariants.md#buffers-uploads-and-terminal-history)
 
 **File-path links (terminal + chat)**: a path an agent prints is clickable on BOTH surfaces and opens the file-preview overlay. ⚠️ ONE pattern (`FILE_PATH_LINK_PATTERN` / `absoluteFilePathPattern()` in constants.js) feeds the xterm link provider AND `_linkifyFilePaths()`, a fresh instance per call (`lastIndex`). The chat linkifier walks TEXT NODES with DOM APIs, never rebuilds sanitized markup as a string. ⚠️ An out-of-workspace path goes through the ATTACHMENT routes (`POST /api/sessions/:id/attachments` with `notify: false`), never by widening `file-content`/`file-raw` or `file-stream-manager`'s `tail -f` allowlist. ⚠️ `TEXT_ATTACHMENT_EXTENSIONS` IS `EDITABLE_EXTENSIONS` (never a second list), and widening READ must never widen RUN: `html`/`htm`/`svg` stay download-only, other text is inert `text/plain`+`nosniff`. Media extensions are single-sourced in `attachment-registry.ts`. ⚠️ **XLSX previews parse in the BROWSER**, never on the server: `spreadsheet-preview.js` fetches the raw route with `?preview=true` (413 above `MAX_XLSX_BROWSER_PREVIEW_BYTES`, 10 MB) and hands the bytes to `spreadsheet-preview-worker.js`, the only place the pinned `exceljs`/`fflate` vendor bundles load (never on page load). `admitXlsx()` caps the ZIP before ExcelJS runs, counting what ExcelJS will EXPAND as well as what it reads (a merge costs its area, a `<col>` past 16384 is refused, validations are never parsed via `ignoreNodes`, and defined names are never expanded: the worker stubs `_definedNames.model`). ⚠️ The INDEX a row or sheet claims is bounded too, since ExcelJS allocates and walks up to it: a `<row r>` outside 1-1048576 and an `xl/workbook.xml` `<sheet sheetId>` above `LIMITS.maxSheetId` (65535) are refused, and `sendTile` reuses the merges read at load (`mergesById`), never `sheet.model`, which rebuilds the whole sheet. ⚠️ The COLUMN index costs the same way (a row's cells live at `_cells[col - 1]`, so one `XFD` cell makes ExcelJS's `eachRow`/`eachCell`/`hasValues` visit 16,384 slots per row): `worksheetMetadata` builds each sheet's row and cell index from the keys that exist (`Object.keys` of `_rows` and `_cells`, skipping falsy and `Null`-type cells as `eachCell({ includeEmpty: false })` does), reads row heights in that pass and merges from `sheet._merges`, and `sendTile` reads cells from that index (`populatedRowsById`); never call ExcelJS's dense `eachRow`/`eachCell` there. `parseThemePalette` returns the default palette for a theme above 64 KB (64 * 1024 characters), since its patterns are quadratic on unclosed tags. ⚠️ Merges are capped per sheet (`LIMITS.maxMergesPerSheet`, 2,000) AND workbook-wide (`LIMITS.maxMerges`, 10,000), refused as `merge-limit` before ExcelJS loads, since ExcelJS's `_mergeCellsInternal` checks each merge against every earlier one on its sheet (quadratic). Every `<numFmt>` in `xl/styles.xml` is read with `readTagAttributes()` and refused (`number-format`) when its decoded `formatCode` is over 255 characters or has a `[` after its last `]`: ExcelJS's `isDateFmt` rescans to the end of the code per unclosed `[` once per numeric cell, and the code is echoed into the notice bar. ⚠️ `formatCellValue` caps every cell's display text at `LIMITS.maxCellTextChars` (1,000, ellipsis, never splitting a surrogate pair) for every value shape (rich text, hyperlink text, formula source, errors), since structured clone copies each tile cell's whole string to the page and the load timeout no longer covers tiles. `richTextPrefix` also visits at most `maxCellTextChars + 1` runs, not only keeps that much text: an empty `<r/>` adds nothing, so a shared string of a million empty runs was walked whole per cell, per tile (56 s a tile). ⚠️ Every part ExcelJS parses (all but the pure-bytes `xl/media/<name>.<ext>`) is also charged per START TAG against `LIMITS.maxElements` (2,000,000, refused as `element-limit`): ExcelJS builds an object per element in sharedStrings, styles, comments, drawings, VML and tables too, and empty stored blocks pad a deflate stream past the ratio cap, so 8.3M empty `<r/>` runs in a 375 KB file cost 570 MB of heap. ⚠️ Admission keys every entry on the name ExcelJS will SEE (`excelJsEntryName()`: JSZip's `.`/`..`/empty-segment resolution, then one leading `/` stripped), refuses two entries that land on one name, and treats anything matching ExcelJS's UNANCHORED `xl/worksheets/sheet<N>.xml` as a worksheet, so `/xl/...` or `xl/./...` cannot skip a counter, and ExcelJS parses only a STORE-only archive rebuilt from the entries admission inflated (`buildAdmittedArchive()`), never the fetched bytes; cell text goes through `textContent`, formulas are never evaluated. Bumping either package or editing the worker/core changes `SPREADSHEET_ASSET_VERSION`, which `npm run check:public-assets` pins. xls/ods stay download-only. → [architecture-invariants#file-path-links-terminal--response-viewer](docs/architecture-invariants.md#file-path-links-terminal--responseLine truncated