feat: enhance CDP bridge management and fix JS falsy returns

- background.js: Add management API, auto-return for JS, refactor new tab capture
- simphtml.py: Fix falsy return value bug, flatten return structure
- agent_loop.py: Simplify UI icons
- manifest.json: Add management permission
- tools_schema: Optimize prompts for web tools
- tmwebdriver_sop.md: Update documentation

assets/tmwd_cdp_bridge/manifest.json

@@ -10,7 +10,8 @@
     "debugger",
     "scripting",
     "alarms",
-    "declarativeNetRequest"
+    "declarativeNetRequest",
+    "management"
   ],
   "host_permissions": ["<all_urls>"],
   "background": {