Summary

Add a dedicated unit test file for DebuggerEndpointHelper to cover endpoint selection, fallback logic, and debugger type detection with stubbed HTTP/HTTPS/DNS dependencies.

Proposed Changes

• Add test/cdp-proxy/debuggerEndpointHelper.test.ts with direct unit tests
• Cover getWSEndpoint returning /json/version webSocketDebuggerUrl when present
• Cover fallback to /json/list including Hermes improved Chrome reload target selection
• Cover fallback to default Metro endpoint when no targets found
• Cover getDebuggerType returning expo vs react-native
• Cover retry/cancellation behavior in retryGetWSEndpoint

Test Plan

• npm test passes with the new test file included

Closes #2705