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

build.ts

@@ -40,6 +40,8 @@ const DEFAULT_BUILD_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',
@@ -145,7 +147,15 @@ if (typeof globalThis.Bun === "undefined") {
   function $(parts, ...args) {
     throw new Error("Bun.$ shell API is not available in Node.js. Use Bun runtime for this feature.");
   }
-  globalThis.Bun = { which, $ };
+  function hash(data, seed) {
+    let h = ((seed || 0) ^ 0x811c9dc5) >>> 0;
+    for (let i = 0; i < data.length; i++) {
+      h ^= data.charCodeAt(i);
+      h = Math.imul(h, 0x01000193) >>> 0;
+    }
+    return h;
+  }
+  globalThis.Bun = { which, $, hash };
 }
 import "./cli.js"
 `