feat: add async error handling to onRequest

[taeold]

We'll now wraps an HTTP handler with a safety net for unhandled errors.

This wrapper catches both synchronous errors and rejected Promises from async handlers. Without this, an unhandled error in an async handler would cause the request to hang until the platform timeout, as Express (v4) does not await handlers.

This is a BREAKING CHANGE in the most technical sense - unhandled errors in async onRequest handlers now immediately return a 500 Internal Server Error instead of hanging until timeout. This may affect clients relying on timeouts (for whatever reason).

[gemini-code-assist]

Summary of Changes

Hello @taeold, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the reliability of HTTP request handlers by implementing robust error handling for asynchronous operations. It introduces a common utility to catch unhandled errors and rejected promises within async handlers, ensuring that instead of requests hanging until a platform timeout, an immediate 500 Internal Server Error is returned. This improvement standardizes error responses and prevents indeterminate request states, making the system more predictable and stable.

Highlights

• New Error Handling Utility: Introduced a new withErrorHandler utility function in src/common/providers/https.ts to centralize the catching of synchronous errors and rejected Promises from async HTTP handlers.
• Integration into onRequest: The withErrorHandler function has been integrated into both v1 (_onRequestWithOptions) and v2 (onRequest) https providers, ensuring consistent error handling across versions.
• Prevention of Hanging Requests: This change prevents async HTTP handlers from causing requests to hang indefinitely on unhandled errors, which was a limitation due to Express (v4) not awaiting handlers.
• Breaking Change Notification: Unhandled errors in async onRequest handlers will now immediately return a 500 Internal Server Error instead of timing out, which is a technical breaking change for clients that might have relied on the previous timeout behavior.
• Comprehensive Testing: New test files (spec/v1/providers/httpsAsync.spec.ts and spec/v2/providers/httpsAsync.spec.ts) have been added to verify the correct behavior of async error handling in both v1 and v2 onRequest functions.

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[gemini-code-assist]

Code Review

This pull request introduces an important improvement by adding a safety net for unhandled errors in async onRequest handlers. The new withErrorHandler wrapper correctly catches both synchronous errors and rejected promises, preventing requests from hanging and instead returning a 500 error. The implementation is clean and applied correctly to both v1 and v2 onRequest functions. The new tests cover the basic success and failure scenarios. I've added a couple of suggestions to make the tests more comprehensive by asserting the HTTP response status and body in the error case.

[jhuleatt]

this is great! might save devs some $$ too if we're preventing long hangs to timeout