[codex] Handle chat run abort lifecycle (#454)

* feat: call upstream stop API when aborting a run

- Modified handleAbort to call POST /v1/runs/{run_id}/stop endpoint
- Use profile-specific upstream URL and API key from gatewayManager
- Add 5-second timeout with error handling and logging
- Keep local abortController.abort() for EventSource cleanup
- Change handleAbort to async method and update call site

This ensures the upstream Hermes gateway is properly notified
when a user aborts a run, allowing graceful termination.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix: close ChatRunSocket connections on shutdown to prevent hanging

- Add close() method to ChatRunSocket to abort all active runs
  and clear session state
- Pass chatRunServer to bindShutdown and close it before
  groupChatServer during shutdown
- This prevents EventSource connections and abort controllers
  from keeping the process alive during nodemon restart

Fixes the "still waiting for sub-process to finish" issue.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* Handle chat run abort lifecycle

---------

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/client/src/components/hermes/chat/ChatInput.vue

@@ -317,6 +317,7 @@ function isImage(type: string): boolean {
           v-if="chatStore.isStreaming"
           size="small"
           type="error"
+          :disabled="chatStore.isAborting"
           @click="chatStore.stopStreaming()"
         >
           {{ t('chat.stop') }}