fix: prevent extension from hanging when embedder service is unavailable

[roomote]

Description

This PR attempts to address Issue #8777 where the extension would get stuck loading indefinitely when the embedder service is unavailable.

Problem

When the CodeIndexManager cannot connect to the embedder service, the extension gets stuck loading and never fully activates until all folders in the VSCode workspace fail. This prevents users from using the extension UI even to fix configuration issues.

Solution

The fix involves two key changes:

1. Non-blocking initialization: Changed the CodeIndexManager initialization from blocking (await) to non-blocking (using .catch()) during extension activation. This allows the extension to fully activate even if the embedder service is unavailable.

2. Timeout for embedder validation: Added a 5-second timeout to the embedder validation process using Promise.race(). This prevents indefinite hanging when trying to connect to an unavailable service.

Changes Made

• Modified src/extension.ts to make CodeIndexManager initialization non-blocking
• Updated src/services/code-index/service-factory.ts to add a 5-second timeout to embedder validation
• Error messages are properly logged to the output channel for debugging

Testing

• All existing tests pass
• Extension now loads successfully even when embedder service is unavailable
• Error messages are displayed in the output log when connection fails

Related Issues

Fixes #8777

Feedback and guidance are welcome!

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Important

Fixes extension hanging by making CodeIndexManager initialization non-blocking and adding a timeout to embedder validation.

• Behavior:
  • CodeIndexManager initialization in src/extension.ts changed to non-blocking using .catch() to prevent extension hanging.
  • Added 5-second timeout to validateEmbedder() in service-factory.ts using Promise.race() to avoid indefinite hanging.
• Logging:
  • Error messages logged to output channel in src/extension.ts for debugging when connection fails.
• Testing:
  • Extension loads successfully even when embedder service is unavailable.
  • All existing tests pass.

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[roomote]

Review Summary

I've reviewed the changes in this PR. The approach successfully makes CodeIndexManager initialization non-blocking and adds a timeout to prevent indefinite hanging when the embedder service is unavailable. However, I found one minor issue with type annotations:

Issues to Address

• Fix type annotation for timeout promise in service-factory.ts (line 99) - the promise only rejects, so Promise<never> would be more accurate than Promise<{ valid: boolean; error: string }>

Follow Along on Roo Code Cloud

[roomote]

The timeout promise is typed as Promise<{ valid: boolean; error: string }> but only ever calls reject(), never resolve(). The type annotation is misleading since this promise will never successfully resolve to that type. Consider using Promise<never> or removing the type annotation entirely to let TypeScript infer it correctly, since the promise only rejects.