fix(bundle): add retry loop to streamUrlToFile for transport failures

[crypticsaiyan]

Summary

streamUrlToFile promised a "bounded retry on transport failures" in its JSDoc but made only one attempt. Transient network blips during downloads caused hard failures, forcing manual re-runs.

The Fix

• Bounded Retry Loop: Added a 3-attempt loop (STREAM_URL_MAX_RETRIES) with a 1s delay for transport or mid-stream pipeline errors.
• Smart Fail-Fast: HTTP 4xx/5xx errors (ApiError) skip retries and fail immediately (e.g., expired presigned URLs will not recover).
• Testability: Added an optional deps.sleep injection for deterministic testing without real-world delays.

Testing

Added 5 tests to src/lib/bundle.test.ts verifying:

• First-attempt success
• Transient recovery (retry-then-succeed)
• Retry exhaustion (TransportError)
• Fast failure on HTTP errors (ApiError)
• Correct injected sleep calls between attempts

Files Changed:

• src/lib/bundle.ts
• src/lib/bundle.test.ts