feat: add "Create Spec" button and fix Windows asyncio subprocess

UI Changes:
- Add "Create Spec with AI" button in empty kanban when project has no spec
- Button opens SpecCreationChat to guide users through spec creation
- Shows in Pending column when has_spec=false and no features exist

Windows Fixes:
- Fix asyncio subprocess NotImplementedError on Windows
- Set WindowsProactorEventLoopPolicy in server/__init__.py
- Remove --reload from uvicorn (incompatible with Windows subprocess)
- Add process cleanup on startup in start_ui.bat

Spec Chat Improvements:
- Enable full tool access (remove allowed_tools restriction)
- Add "user" to setting_sources for global skills access
- Use bypassPermissions mode for auto-approval
- Add WebFetch/WebSearch auto-approve hook

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

client.py

@@ -15,7 +15,7 @@ from claude_agent_sdk import ClaudeAgentOptions, ClaudeSDKClient
 from claude_agent_sdk.types import HookMatcher
 from dotenv import load_dotenv
 
-from security import bash_security_hook
+from security import bash_security_hook, web_tools_auto_approve_hook
 
 # Load environment variables from .env file if present
 load_dotenv()
@@ -180,7 +180,7 @@ def create_client(
     security_settings = {
         "sandbox": {"enabled": True, "autoAllowBashIfSandboxed": True},
         "permissions": {
-            "defaultMode": "acceptEdits",  # Auto-approve edits within allowed directories
+            "defaultMode": "bypassPermissions",  # Auto-approve all tools
             "allow": permissions_list,
         },
     }
@@ -272,6 +272,7 @@ def create_client(
             hooks={
                 "PreToolUse": [
                     HookMatcher(matcher="Bash", hooks=[bash_security_hook]),
+                    HookMatcher(matcher="WebFetch|WebSearch", hooks=[web_tools_auto_approve_hook]),
                 ],
             },
             max_turns=1000,