docs: verify #41 already implemented

Fixes #59

The footer links to /about but the repo ships about.html. On a plain static server this results in a 404. Changed to /about.html so the link resolves correctly.

docs/issue-41-verification.md

@@ -0,0 +1,32 @@
+# Issue #41 Verification
+
+Status: already implemented on main
+
+Issue:
+- #41 [P3] Service worker: cache crisis resources for offline
+
+Acceptance criteria check:
+1. Passed — offline page includes 988 call button, Crisis Text Line, and grounding techniques
+2. Passed — service worker precaches `crisis-offline.html`
+3. Passed — phone number is clickable via `href="tel:988"`
+4. Passed — navigation timeout + offline fallback support intermittent connections
+
+Evidence:
+- `sw.js` precaches `/crisis-offline.html`
+- `sw.js` contains `NAVIGATION_TIMEOUT_MS` and `AbortController`
+- `crisis-offline.html` contains:
+  - `href="tel:988"`
+  - Crisis Text Line / `741741`
+  - grounding prompts for 5-4-3-2-1
+- `tests/test_service_worker_offline.py` already exists on main and passes
+
+Verification run from fresh main clone:
+- `python3 -m pytest tests/test_service_worker_offline.py -q`
+  - `10 passed`
+
+Prior implementation trail:
+- Issue comment already states the core implementation is complete on main
+- Closed PR #122 documented the already-complete implementation and added the offline guarantees test coverage that is now present on main
+
+Recommendation:
+- Close issue #41 as already implemented on main.