[upstream/eca] State machine race on promptStop

[ssjoleary]

Note: This is a server-side bug (lives in editor-code-assistant/eca, not eca-nvim). Tracked here for our own visibility.

Where

eca/src/eca/features/chat/tool_calls.clj:480 in transition_tool_call_BANG_

Symptom

Invalid state transition exception logged after chat/promptStop:

:current-status :cleanup
:event :tool-prepare
:valid-events (:cleanup-finished :stop-requested)

Why

Anthropic stream delivers :tool-prepare chunks after server enters :cleanup state. The state machine rejects them.

Fix (upstream)

Either:

• Silently discard tool-prepare events during :cleanup state, or
• Add :tool-prepare to valid-events set for that transition

Impact

Cosmetic — stop still works. Just noisy exceptions in server logs.

Found

During manual testing of editor-code-assistant#63 (chat/promptStop implementation).