revert: PR #2666 ACP retry/reconnect logic

[tanzhenxin]

Summary

• Reverts feat(vscode): add retry logic and auto-reconnect for ACP connection #2666

The stdout readiness check introduced in #2666 doesn't work with the CLI relaunch wrapper. The CLI spawns a child process via relaunchAppInChildProcess(), and the actual ACP stdout data comes from the grandchild process — the parent never writes to stdout, causing every connection attempt to time out after 10s.

This restores the v0.13.2 behavior (simple 1s delay) which works reliably.

Test plan

• Install the VSCode extension and verify it connects on startup without timeout errors
• Verify no SIGTERM errors in the extension output channel

[pomelo-nwu]

LGTM

[github-actions]

📋 Review Summary

This PR reverts the retry/reconnect logic introduced in #2666, which caused timeout issues when the CLI relaunch wrapper spawns a grandchild process. The revert restores the simpler v0.13.2 behavior with a 1-second delay instead of the complex stdout readiness check. Overall, this is a well-scoped revert that addresses a real architectural mismatch between the readiness check and the process hierarchy.

🔍 General Feedback

• The revert is clean and properly removes all related retry/reconnect infrastructure across 6 files
• Good test coverage cleanup - removed tests are specifically for the reverted functionality
• The simplification from a 10-second stdout readiness check back to a 1-second delay is pragmatic given the grandchild process architecture
• Positive that the PR includes a clear test plan for verification

🎯 Specific Feedback

🟡 High

• File: packages/vscode-ide-companion/src/services/acpConnection.ts:184 - The change from a 10-second stdout readiness check to a fixed 1-second delay (setTimeout) trades reliability for compatibility. While this fixes the grandchild process issue, consider adding a comment explaining why the stdout check doesn't work with the relaunch wrapper architecture, so future maintainers understand this isn't just a lazy implementation.

• File: packages/vscode-ide-companion/src/services/qwenAgentManager.ts - The removal of the onDisconnected handler means there's no automatic reconnection logic at all now. If the ACP process crashes unexpectedly, users will need to manually reconnect. Consider whether a simpler reconnection strategy (without the complex retry logic) might still be valuable.

🟢 Medium

• File: packages/vscode-ide-companion/src/services/acpConnection.ts:368-383 - The initialize timeout handling was also removed (lines 380-397 in the original). The comment says "Race the SDK initialize against process exit" but the timeout promise that enforced the 15-second limit is now gone. This means the initialize could potentially hang indefinitely. Consider keeping the timeout logic even without the retry infrastructure.

• File: packages/vscode-ide-companion/src/webview/providers/WebViewProvider.ts:882-884 - The error message was simplified from showing a "Retry Connection" button to just a warning message. This reduces user agency when connection fails. The old flow allowed users to retry directly from the notification.

🔵 Low

• File: packages/vscode-ide-companion/src/services/acpConnection.ts - Consider adding a TODO or FIXME comment near the 1-second delay noting that a more robust readiness detection mechanism might be desirable in the future, perhaps one that works with the grandchild process architecture.

• File: packages/vscode-ide-companion/src/services/qwenConnectionHandler.test.ts - Test file could benefit from a comment explaining why the tests were simplified (reverting from connectWithRetry to connect), to help future maintainers understand the evolution.

✅ Highlights

• Clean revert that removes all traces of the retry/reconnect infrastructure consistently across implementation and test files
• Good identification of the root cause: the parent process never writes to stdout when using relaunchAppInChildProcess(), making the stdout readiness check fundamentally incompatible
• The PR body clearly explains the technical reason for the revert and includes a test plan
• Removing 465 lines while only adding 19 shows good discipline in not over-engineering the solution