Greptile Summary

This PR fixes a gateway crash caused by ProxyGatewayPlugin wrapping the bare "fetch failed" Fetch API error into a higher-level message (e.g. "Failed to get gateway information from Discord: fetch failed"), which the old exact-match check missed, leading to process.exit(1). The fix adds "fetch failed" to TRANSIENT_NETWORK_MESSAGE_SNIPPETS so the existing case-insensitive substring logic catches both bare and wrapped forms, and removes the now-redundant exact-match checks.

Key changes:

• "fetch failed" added to TRANSIENT_NETWORK_MESSAGE_SNIPPETS; the two prior exact-match checks (instanceof TypeError && message === "fetch failed" and standalone message === "fetch failed") are removed as they are now strictly subsumed
• SSL/TLS error codes (EPROTO, ERR_SSL_WRONG_VERSION_NUMBER, ERR_SSL_PROTOCOL_RETURNED_AN_ERROR) and message snippets (tlsv1 alert, ssl routines, packet length too long, write eproto) are bundled in the same change
• A test case for the wrapped Discord error is added to the transient-cases suite

The solution is straightforward: substring matching with "fetch failed" is a strict superset of the old exact-match logic. All 39 existing tests pass, and a new test for the reported scenario is included.

Confidence Score: 5/5

• Safe to merge. The fix is logically sound, all 39 existing tests pass, and the reported scenario is now covered by a new test.
• The change is a straightforward fix that strictly extends the previous behavior to catch wrapped error messages. The substring matching correctly handles both bare "fetch failed" errors and wrapped variants like "Failed to get gateway information from Discord: fetch failed". The implementation removes redundant exact-match checks that are now subsumed by the broader snippet matching. Test coverage is comprehensive with both existing test suites passing and new tests added for the reported scenario. No functional issues or regressions identified.
• No files require special attention.

_{Last reviewed commit: 11fa4e9}

PR #38530 - fix(gateway): classify wrapped "fetch failed" messages as transient network errors (#38530)

Merged after verification.

• Merge commit: 1a022a3
• Verified: pnpm build, pnpm check, pnpm test:macmini
• Autoland updates:
  M CHANGELOG.md
  M src/infra/unhandled-rejections.ts
  M src/infra/unhandled-rejections.test.ts
  M src/infra/unhandled-rejections.fatal-detection.test.ts
• Rationale:
  Addressed open review thread by narrowing fetch-failed matching to transport-oriented wrapped suffixes, added positive/negative regressions, and fixed TS typing in fatal-detection transient test cases.
• Changelog: CHANGELOG.md updated=true required=true opt_out=false