feat: add model health monitoring and trace context logging

[vlordier]

Add ModelStatus struct, get_status method, and trace_id logging

[Copilot]

Pull request overview

Adds health/status reporting for the currently selected inference model and introduces per-request trace ID logging to improve observability in the LocalCowork Tauri app.

Changes:

• Adds a ModelStatus struct for serializable model health/status reporting.
• Introduces InferenceClient::get_status() to return endpoint + health details.
• Logs a generated trace_id at the start of send_message() for log correlation.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
examples/localcowork/src-tauri/src/inference/types.rs	Adds ModelStatus type (serde-serializable) for health monitoring consumers.
examples/localcowork/src-tauri/src/inference/client.rs	Adds get_status() API and extends tests with an LM Studio model config case.
examples/localcowork/src-tauri/src/commands/chat.rs	Generates and logs a trace_id at the beginning of message processing.

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[Copilot]

This uses CONNECT_TIMEOUT (documented as a TCP connect timeout) as a per-request total timeout via .timeout(CONNECT_TIMEOUT). That’s confusing and easy to misuse because reqwest::RequestBuilder::timeout applies to the entire request/response. Consider introducing a dedicated short HEALTH_CHECK_TIMEOUT (or similar) for health/status calls, or updating the constant name/doc to match its actual use here.

[Copilot]

trace_id is generated but only attached to a single log record. If the goal is request-level correlation across subsequent logs, consider creating a tracing span that includes trace_id (and entering it for the rest of the function) so downstream tracing::info!/debug! calls inherit the same context. Also, truncating to 8 hex chars (32 bits) increases the chance of collisions in logs; using the full UUID or a longer prefix would reduce that risk.

Suggested change

	let trace_id = uuid::Uuid::new_v4().to_string()[..8].to_string();
	tracing::info!(trace_id = %trace_id, session_id = %session_id, content_len = content.len(), "starting message processing");
	let trace_id = Uuid::new_v4().to_string();
	// Create a span so all subsequent logs inherit the same trace_id/session_id context.
	let span = tracing::info_span!("send_message", trace_id = %trace_id, session_id = %session_id);
	let _span_guard = span.enter();
	tracing::info!(content_len = content.len(), "starting message processing");

[Copilot]

get_status sets model_name: None for non-2xx and transport errors, even though the client already knows the configured model name/key. This makes the status payload less useful for UIs/health dashboards because you lose which model is unhealthy. Consider always populating model_name (e.g., from current_model.model_name falling back to current_model_key) and reserve error/healthy for the health signal.

[Paulescu]

Closing this one. The three changes (ModelStatus, get_status, trace_id) each land as a primitive with no consumer, so nothing in the app actually exercises them.

get_status is dead code. No Tauri command, chat handler, or orchestrator path calls it. ModelStatus is referenced only as the return type of the method that nobody invokes. For a "health monitoring" feature, the integration is the point — a Tauri command like get_model_status that the frontend calls, ideally with a polling story or an event when health changes.

trace_id is logged once and never propagated. send_message generates a trace_id and emits a single tracing::info! with it, then the rest of the function logs without the field. There's nothing to correlate. The idiomatic shape is either #[tracing::instrument(fields(trace_id))] on send_message or let _span = tracing::info_span!("send_message", trace_id = %trace_id).entered(); at the top of the body — both attach the field to every event in the span automatically.

Hardcodes /models instead of using runtime.health_check. _models/config.yaml declares per-runtime health endpoints (Ollama: /api/tags, llama_cpp: /health, lmstudio: /v1/models). get_status unconditionally hits {base_url}/models, which 404s on Ollama. Read the configured health_check URL for the runtime, fall back to /v1/models only if absent.

Smuggled content from #53. The lmstudio-model test fixture and test_lmstudio_model_config test in inference/client.rs are the same lines added by #53. Not blocking on their own, but the partial overlap will conflict on rebase. Once #53 is resolved, drop those hunks from this branch.

Smaller nits:

• uuid::Uuid::new_v4().to_string()[..8].to_string() is fragile and gives 32 bits of entropy. If short IDs are wanted, use a counter or nanoid. The [..8] is ASCII-safe only because of UUID's hex format.
• The multi-line assert! reformatting in types.rs is unrelated rustfmt churn.
• PR description is one sentence with no motivation or integration plan.

If you want to resubmit, the rule of thumb is: ship the primitive and its first consumer in the same PR. Add get_status, expose it as get_model_status Tauri command, and wire the frontend (or at least an integration point) that calls it. Add trace_id propagation via a span on the request handler. With those, this becomes a reviewable feature.