Hermes Web UI — Sprints 11-14: multi-provider models, settings, session QoL, alerts, polish

Sprint 11 (v0.13): multi-provider model support, streaming smoothness
- Dynamic model dropdown populated from configured API keys (OpenAI, Anthropic,
  Google, DeepSeek, GLM, Kimi, MiniMax, OpenRouter, Nous Portal)
- Scroll pinning during streaming (no forced scroll when user has scrolled up)
- All route handlers extracted to api/routes.py (server.py now ~76 lines)

Sprint 12 (v0.14): settings panel, SSE reconnect, session QoL
- Settings panel (gear icon) -- persist default model and workspace server-side
- SSE auto-reconnect on network blips
- Pin/star sessions to top of sidebar
- Import session from JSON export

Sprint 13 (v0.15): cron alerts, background errors, session duplicate, tab title
- Cron completion alerts: toast per completion + unread badge on Tasks tab
- Background agent error banner when a non-active session errors mid-stream
- Session duplicate button
- Browser tab title reflects active session name

Sprint 14 (v0.16): Mermaid diagrams, file ops, session archive/tags, timestamps
- Mermaid diagram rendering inline (dark theme, lazy CDN load)
- File rename (double-click in file tree) and create folder
- Session archive (hide without deleting, toggle to show)
- Session tags -- #hashtag in title becomes colored chip + click-to-filter
- Message timestamps (HH:MM on hover, full date as tooltip)

Test suite: 224 tests across 14 sprint files + regression gate, 0 failures.

tests/test_sprint1.py

@@ -1,5 +1,5 @@
 """
-Sprint 1 test suite for the Hermes WebUI.
+Sprint 1 test suite for the Hermes Web UI.
 
 Tests use the ISOLATED test server running on http://127.0.0.1:8788.
 Production server (port 8787) and your real conversations are never touched.