chore: merge main into feature branch

Resolved conflicts:
- VERSION: keep 0.9.0 (ours supersedes 0.8.6)
- CHANGELOG: prepend 0.9.0 above new 0.8.6 entry
- gen-skill-docs.ts: integrate telemetry (pending finalize, prompt)
  into decomposed sub-functions with host-aware paths
- gen-skill-docs.test.ts: keep both Codex generation and telemetry tests

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

browse/SKILL.md

@@ -33,8 +33,15 @@ echo "BRANCH: $_BRANCH"
 echo "PROACTIVE: $_PROACTIVE"
 _LAKE_SEEN=$([ -f ~/.gstack/.completeness-intro-seen ] && echo "yes" || echo "no")
 echo "LAKE_INTRO: $_LAKE_SEEN"
+_TEL=$(~/.claude/skills/gstack/bin/gstack-config get telemetry 2>/dev/null || true)
+_TEL_PROMPTED=$([ -f ~/.gstack/.telemetry-prompted ] && echo "yes" || echo "no")
+_TEL_START=$(date +%s)
+_SESSION_ID="$$-$(date +%s)"
+echo "TELEMETRY: ${_TEL:-off}"
+echo "TEL_PROMPTED: $_TEL_PROMPTED"
 mkdir -p ~/.gstack/analytics
 echo '{"skill":"browse","ts":"'$(date -u +%Y-%m-%dT%H:%M:%SZ)'","repo":"'$(basename "$(git rev-parse --show-toplevel 2>/dev/null)" 2>/dev/null || echo "unknown")'"}'  >> ~/.gstack/analytics/skill-usage.jsonl 2>/dev/null || true
+for _PF in ~/.gstack/analytics/.pending-*; do [ -f "$_PF" ] && ~/.claude/skills/gstack/bin/gstack-telemetry-log --event-type skill_run --skill _pending_finalize --outcome unknown --session-id "$_SESSION_ID" 2>/dev/null || true; break; done
 ```
 
 If `PROACTIVE` is `"false"`, do not proactively suggest gstack skills — only invoke
@@ -54,6 +61,27 @@ touch ~/.gstack/.completeness-intro-seen
 
 Only run `open` if the user says yes. Always run `touch` to mark as seen. This only happens once.
 
+If `TEL_PROMPTED` is `no` AND `LAKE_INTRO` is `yes`: After the lake intro is handled,
+ask the user about telemetry. Use AskUserQuestion:
+
+> gstack can share anonymous usage data (which skills you use, how long they take, crash info)
+> to help improve the project. No code, file paths, or repo names are ever sent.
+> Change anytime with `gstack-config set telemetry off`.
+
+Options:
+- A) Yes, share anonymous data (recommended)
+- B) No thanks
+
+If A: run `~/.claude/skills/gstack/bin/gstack-config set telemetry anonymous`
+If B: run `~/.claude/skills/gstack/bin/gstack-config set telemetry off`
+
+Always run:
+```bash
+touch ~/.gstack/.telemetry-prompted
+```
+
+This only happens once. If `TEL_PROMPTED` is `yes`, skip this entirely.
+
 ## AskUserQuestion Format
 
 **ALWAYS follow this structure for every AskUserQuestion call:**
@@ -153,6 +181,27 @@ ATTEMPTED: [what you tried]
 RECOMMENDATION: [what the user should do next]
 ```
 
+## Telemetry (run last)
+
+After the skill workflow completes (success, error, or abort), log the telemetry event.
+Determine the skill name from the `name:` field in this file's YAML frontmatter.
+Determine the outcome from the workflow result (success if completed normally, error
+if it failed, abort if the user interrupted). Run this bash:
+
+```bash
+_TEL_END=$(date +%s)
+_TEL_DUR=$(( _TEL_END - _TEL_START ))
+rm -f ~/.gstack/analytics/.pending-"$_SESSION_ID" 2>/dev/null || true
+~/.claude/skills/gstack/bin/gstack-telemetry-log \
+  --skill "SKILL_NAME" --duration "$_TEL_DUR" --outcome "OUTCOME" \
+  --used-browse "USED_BROWSE" --session-id "$_SESSION_ID" 2>/dev/null &
+```
+
+Replace `SKILL_NAME` with the actual skill name from frontmatter, `OUTCOME` with
+success/error/abort, and `USED_BROWSE` with true/false based on whether `$B` was used.
+If you cannot determine the outcome, use "unknown". This runs in the background and
+never blocks the user.
+
 # browse: QA Testing & Dogfooding
 
 Persistent headless Chromium. First call auto-starts (~3s), then ~100ms per command.