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>

src/index.ts

@@ -93,7 +93,17 @@ async function run(options: RunOptions = {}) {
       ),
     },
   });
-  server.addHook("preHandler", apiKeyAuth(config));
+  // Add async preHandler hook for authentication
+  server.addHook("preHandler", async (req, reply) => {
+    return new Promise((resolve, reject) => {
+      const done = (err?: Error) => {
+        if (err) reject(err);
+        else resolve();
+      };
+      // Call the async auth function
+      apiKeyAuth(config)(req, reply, done).catch(reject);
+    });
+  });
   server.addHook("preHandler", async (req, reply) => {
     if(req.url.startsWith("/v1/messages")) {
       router(req, reply, config)