feat: integrate 5 feature branches, upstream fixes, and MIME detection fix

Squashed 5 commits:

Features (from 5 feature branches):
- MCP fix, pipe mute, stub recovery
- KAIROS activation, openclaw autonomy
- Daemon/job command hierarchy + cross-platform bg engine

Upstream fixes:
- fix: Bun.hash compatibility
- chore: chrome dependency update
- docs: browser support guide

MIME detection fix:
- Screenshot detectMimeFromBase64(): decode raw bytes from base64
  instead of broken charCodeAt comparison
- Fixes API 400 on Windows (JPEG) and macOS (PNG) screenshots

scripts/dev.ts

@@ -47,6 +47,8 @@ const DEFAULT_FEATURES = [
   "KAIROS",
   "COORDINATOR_MODE",
   "LAN_PIPES",
+  "BG_SESSIONS",
+  "TEMPLATES",
   // "REVIEW_ARTIFACT", // API 请求无响应，需进一步排查 schema 兼容性
   // P3: poor mode (disable extract_memories + prompt_suggestion)
   "POOR",