feat: Implement temporary API key based on system UUID for UI access

This commit introduces a new authentication mechanism for the web UI.
Instead of requiring a pre-configured API key, a temporary API key is
generated based on the system's UUID. This key is passed to the UI
as a URL parameter and used for API requests.

Changes:
- Added a new utility to get the system UUID and generate a temporary API key.
- Modified the `ccr ui` command to generate and pass the temporary API key.
- Updated the authentication middleware to validate the temporary API key.
- Adjusted the frontend to use the temporary API key from the URL.
- Added a dedicated endpoint to test API access without modifying data.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

ui/src/components/ConfigProvider.tsx

@@ -128,6 +128,20 @@ export function ConfigProvider({ children }: ConfigProviderProps) {
     fetchConfig();
   }, [hasFetched, apiKey]);
 
+  // Check if user has full access
+  useEffect(() => {
+    const checkAccess = async () => {
+      if (config) {
+        const hasFullAccess = await api.checkFullAccess();
+        // Store access level in a global state or context if needed
+        // For now, we'll just log it
+        console.log('User has full access:', hasFullAccess);
+      }
+    };
+    
+    checkAccess();
+  }, [config]);
+
   return (
     <ConfigContext.Provider value={{ config, setConfig, error }}>
       {children}