[pcbeingused333]

Fixes #176

generateTitle returned null without a trace for several different causes, so a session that kept its placeholder title gave no hint why. It now logs one console.warn line per failed attempt with the session id, the provider id, the model and the reason:

• no provider, no base URL or API key, or no model to use
• the upstream request failed: HTTP status and a short excerpt of the error (a 400 for an unknown model id now shows up)
• the reply has no text block
• the reply is not a usable title: a short excerpt of the reply
• any exception, replacing the empty catch

The return value and the placeholder title behave as before. generateTitle takes an optional sessionId for the log line; the WebSocket handler passes it.

Tests in title-service.test.ts cover an upstream 400, a non-title reply and a missing provider; they fail without the change. bun test for that file and tsc --noEmit pass.

This change was prepared with Claude Code (AI-assisted); the tests above were run.

🤖 Generated with Claude Code

[GoDiao]

Thanks @pcbeingused333, this is exactly what #176 asked for! One line per failed attempt with the session, provider, model and reason, the empty catch gone, and the return value unchanged. We checked that the three new tests fail on main and that they restore console.warn and stop their servers.

Approving. Thanks again!