Address PR #10 review feedback

[GordonBeeming]

Summary

• Catch OperationCanceledException explicitly in the SignalR reconnection loop so shutdown logs cleanly instead of appearing as a reconnection failure
• Remove Process.Dispose() from HealthCheckAsync crash detection to avoid racing with SpawnProcessAsync/MonitorAdoptedProcessAsync that may still hold the Process handle

Test plan

• dotnet build -- builds clean
• dotnet test -- all tests pass
• Verify agent shuts down cleanly without noisy reconnection warnings in logs

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR addresses prior review feedback by making agent shutdown/reconnect behavior cleaner and avoiding a potential race when detecting crashed sessions.

Changes:

• Catch OperationCanceledException during the SignalR manual reconnection loop to avoid logging shutdown as a reconnection failure.
• Stop disposing the Process handle inside SessionManager.HealthCheckAsync crash detection to avoid races with code awaiting WaitForExitAsync().

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/ClaudeNest.Agent/Services/SignalRConnectionManager.cs	Adds explicit cancellation handling in the reconnection loop for cleaner shutdown logging.
src/ClaudeNest.Agent/Services/SessionManager.cs	Removes Process.Dispose() (and related behavior) from health-check crash detection to avoid handle races.

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[Copilot]

The new comment says HealthCheckAsync will "clear process reference", but the code no longer clears session.Process (and likely must not, since SpawnProcessAsync/MonitorAdoptedProcessAsync may still use that instance). Please update the comment to accurately describe the behavior (e.g., that we intentionally keep the Process reference and avoid disposing it here, letting the owning path/cleanup handle disposal).

Suggested change

	// Process no longer exists — mark session as crashed and clear process reference.
	// Don't dispose Process here as SpawnProcessAsync/MonitorAdoptedProcessAsync may
	// still be awaiting WaitForExitAsync() on the same instance. Let the owning code
	// path handle disposal; the 1-hour cleanup will catch any stragglers.
	// Process no longer exists — mark session as crashed.
	// Intentionally keep the existing Process reference and avoid disposing it here,
	// as SpawnProcessAsync/MonitorAdoptedProcessAsync may still be awaiting
	// WaitForExitAsync() on the same instance. Let the owning code path handle
	// disposal; the 1-hour cleanup below will remove the session and dispose Process.