fix(copilot): Free plan usage, tall answers in agent read, page-key fallback, review nits

Review of 8659ba25..be987fbb:

- Usage: a Free account answers premium_interactions {entitlement: 0, remaining: 0,
  percent_remaining: 0, unlimited: false, has_quota: false}, which read as 100% used. The parser now
  returns null when has_quota is false or the entitlement is not positive, with that payload as a
  fixture. Free meters chat (200) and completions (2000) too, so the comment no longer says they
  are unlimited on every plan.
- agent read: rows were skipped until a `❯ <prompt>` row, so an answer taller than the pane
  (prompt scrolled off the top) read as "". With no prompt row AND no banner / trust dialog on
  screen, the rows above the composer are now the tail of the last answer. Text typed in the
  composer (a prompt-shaped row between the two rules) is not a prompt row.
- Page keys: measured on 1.0.95 in tmux that Copilot pages on PageUp/PageDown (three PageUp moved
  lines 109-140 to 010-042, PageDown returned) as well as on SGR wheel reports, so copilot joins
  claude and opencode in _localScrollbackIsHollow(); the stale-tracking-flag fallback the comment
  and docs describe is now true, for the main pane and a TerminalTile (same function), with tests.
- X-GitHub-Api-Version is 2022-11-28, a version GitHub supports (verified against the live
  endpoint); readPlanUsageTelemetryEnabled() is checked before isCopilotAvailable() so a switched-off
  chip skips the resolver probe too.
- Palette label for Copilot in panels-ui.js; stale comments in types/session.ts and stock.ts.
- Docs: Past Sessions continues with --continue (resumeSessionId is for API callers), nothing sets
  continueSession on a respawn, and only a tab name the user set is passed as --name; the usage
  wording for Free; the wheel and mouse-strip paragraphs in CLAUDE.md and
  architecture-invariants; the changeset describes the whole feature.

src/config/cli-registry/stock.ts

@@ -1655,7 +1655,8 @@ const OMP: CliEntry = {
 // GitHub Copilot CLI (`copilot`, github/copilot-cli, npm @github/copilot). Measured on a live
 // 1.0.94 pane inside tmux (capture-pane through real turns, a shell tool call and /model,
 // 2026-10-09). It is an ALTERNATE-SCREEN TUI with mouse tracking on (tmux `alternate_on=1`,
-// `mouse_any_flag=1`, `history_size=0`), so it joins grok in the tmux-attach-time strip only.
+// `mouse_any_flag=1`, `history_size=0`), so like opencode its mouse DECSETs are stripped
+// (`altScreen: 'strip-mux-and-mouse'` below): a drag selects locally and the wheel is forwarded.
 // Keystrokes sent with `tmux send-keys` reach its composer and a shell tool call completes
 // inside tmux, which github/copilot-cli#4180 (a driven PTY ignoring input) and #4223 (a shell
 // command never reported done under tmux) say they do not on 1.0.70 to 1.0.74: neither
@@ -1756,6 +1757,10 @@ const COPILOT: CliEntry = {
     // (`cliMouseTracking`). Same shape and reason as opencode. The wheel keeps working because
     // `_shouldForwardWheelToApp` forwards it as SGR reports while the CLI is tracking.
     altScreen: 'strip-mux-and-mouse',
+    // Pages its own transcript on PageUp/PageDown (1.0.95, measured in tmux: three PageUp moved
+    // lines 109-140 to 010-042 and PageDown returned). This is the fallback when the
+    // wheel-forward flag is stale after a server restart, so the wheel and a swipe never go dead.
+    transcriptPageKeys: true,
     echo: { policy: 'buffer', anchor: { kind: 'cursor' } },
     // What `codeman agent spawn` waits for. The composer's footer hint, NOT the `❯` glyph: the
     // folder-trust dialog draws `❯ 1. Yes` for its selected row, so the glyph would call a worker

src/types/session.ts

@@ -546,7 +546,10 @@ export interface CopilotConfig {
   allowAll?: boolean;
   /** Resume the most recent session (--continue). Skipped when resumeSessionId is set. */
   continueSession?: boolean;
-  /** Resume a specific session by ID (--resume=<id>). Ids only, never names. */
+  /**
+   * Resume a specific session (--resume <value>): an id, id prefix or session name, as ONE plain word
+   * starting with a letter or digit (a leading `-` would make the value its own flag).
+   */
   resumeSessionId?: string;
 }
 

src/web/public/panels-ui.js

@@ -533,7 +533,7 @@ Object.assign(CodemanApp.prototype, {
 
   _buildCommandPaletteNewSessionItem(query = '') {
     const mode = this.runMode || this._runMode || 'claude';
-    const labels = { claude: 'Claude', opencode: 'OpenCode', codex: 'Codex', gemini: 'Gemini', antigravity: 'Antigravity', pi: 'Pi', grok: 'Grok', deepseek: 'DeepSeek', omp: 'OMP' };
+    const labels = { claude: 'Claude', opencode: 'OpenCode', codex: 'Codex', gemini: 'Gemini', antigravity: 'Antigravity', pi: 'Pi', grok: 'Grok', deepseek: 'DeepSeek', omp: 'OMP', copilot: 'Copilot' };
     const caseName = this._findCommandPaletteCaseMatch(query) || document.getElementById('quickStartCase')?.value || 'testcase';
     return {
       id: 'new-session',

src/web/response-viewer-transcript.ts

@@ -30,6 +30,12 @@ interface PaneDialect {
   ignore: RegExp[];
   /** Furniture drawn at the end of a row (a scrollbar gutter), removed before anything else reads it. */
   lineTrailer?: RegExp;
+  /**
+   * Text that is on screen only before the first prompt has scrolled the screen: the banner, a
+   * trust dialog. Its presence is how "nothing has been asked yet" is told apart from "the prompt
+   * row has scrolled off the top".
+   */
+  startup: RegExp[];
 }
 
 const PANE_DIALECTS: Record<string, PaneDialect> = {
@@ -52,6 +58,7 @@ const PANE_DIALECTS: Record<string, PaneDialect> = {
     ignore: [/^\s*❯\s*$/],
     // The right-hand scrollbar gutter, `┃` on a row (or alone on a blank one).
     lineTrailer: /\s*[┃▐]\s*$/,
+    startup: [/Copilot v\d+\.\d+\.\d+ uses AI/, /Confirm folder trust/, /Do you trust the files in this folder/],
   },
 };
 
@@ -320,12 +327,23 @@ export function transcriptNeedsScreenCapture(mode: string | null | undefined): b
  * Segment a pane that has its own dialect. Everything before the first prompt is the banner (or a
  * trust dialog) and is dropped, so a session that has not been asked anything answers "nothing
  * yet" rather than serving its logo as a reply.
+ *
+ * The screen is all there is to read, so a long answer scrolls the prompt row off the top. When no
+ * prompt row is on screen AND no startup text is either, the session has already been asked
+ * something: the rows above the composer are the tail of the last answer, not "nothing yet".
  */
 function parseDialectTranscript(cleaned: string, dialect: PaneDialect): ResponseViewerTranscriptBlock[] {
   const blocks: ResponseViewerTranscriptBlock[] = [];
   let kind: ResponseViewerTranscriptKind | null = null;
   let current: string[] = [];
-  let sawPrompt = false;
+  const rows = cleaned.split('\n').map((row) => (dialect.lineTrailer ? row.replace(dialect.lineTrailer, '') : row));
+  // The composer sits between two rules and holds whatever is typed but not sent. That is not a
+  // prompt row: otherwise typing under a tall answer would make the answer's tail read as banner.
+  const isComposerRow = (i: number) =>
+    i > 0 && i < rows.length - 1 && isDividerOnlyLine(rows[i - 1] ?? '') && isDividerOnlyLine(rows[i + 1] ?? '');
+  const hasPrompt = rows.some((row, i) => dialect.prompt.test(row) && !isComposerRow(i));
+  const startupVisible = rows.some((row) => dialect.startup.some((re) => re.test(row)));
+  let sawPrompt = !hasPrompt && !startupVisible;
 
   const flush = () => {
     if (sawPrompt) pushBlock(blocks, kind, current);
@@ -333,13 +351,8 @@ function parseDialectTranscript(cleaned: string, dialect: PaneDialect): Response
     current = [];
   };
 
-  for (const rawLine of cleaned.split('\n')) {
-    const line = dialect.lineTrailer ? rawLine.replace(dialect.lineTrailer, '') : rawLine;
-    if (isDividerOnlyLine(line)) {
-      flush();
-      continue;
-    }
-    if (dialect.ignore.some((re) => re.test(line))) {
+  for (const [index, line] of rows.entries()) {
+    if (isDividerOnlyLine(line) || isComposerRow(index) || dialect.ignore.some((re) => re.test(line))) {
       flush();
       continue;
     }