fix(ios): devsupport IPv6 host parsing for packager and inspector

[hannojg]

Summary:

When Metro host is an IPv6, iOS dev-support had two parsing issues, causing SIGABRTs:

1. RCTPackagerConnection parsed host:port by splitting on :, which breaks IPv6 literals and can build an invalid websocket URL for /message.
2. RCTInspectorDevServerHelper used NSURL.host directly to compose host[:port]. For IPv6, NSURL.host is unbracketed, producing an invalid authority for inspector endpoints.

Changes:

• RCTPackagerConnection: parse host/port via NSURLComponents from a synthesized URL instead of splitting by :.
• RCTInspectorDevServerHelper: re-add IPv6 brackets when composing authority strings from NSURL.host.

Changelog:

[IOS] [FIXED] - Fix iOS dev-support IPv6 handling for packager and inspector connections.

Test Plan:

• Built RNTester Debug (Hermes + New Architecture) for iOS simulator.
• Started Metro on IPv6:
  • RCT_METRO_PORT=8088 yarn --cwd packages/rn-tester start --host :: --port 8088
• Launched RNTester with IPv6 Metro host in settings:
  • RCT_packager_scheme = http
  • RCT_jsLocation = [2a02:...]:8088
• Verified in logs:
  • http://[2a02:...]:8088/status returns 200
  • bundle loads from http://[2a02:...]:8088/js/RNTesterApp.ios.bundle?...
• Verified app remains running and renders RNTester UI (no SIGABRT in packager/inspector startup paths).

[cipolleschi]

Code looks good to me.

[meta-codesync]

@cipolleschi has imported this pull request. If you are a Meta employee, you can view this in D95564862.

[hannojg]

Hey, anything i can do to help land this? 🙈

[github-actions]

Warning

JavaScript API change detected

This PR commits an update to ReactNativeApi.d.ts, indicating a change to React Native's public JavaScript API.

• Please include a clear changelog message.
• This change will be subject to additional review.

This change was flagged as: POTENTIALLY_BREAKING

[hannojg]

Weird, it does not 😅 (i guess somebody is testing that action right now)

[cortinico]

Out of curiousity @hannojg, have you tested Android also against IPv6 bundlers?

[cortinico]

Review automatically exported from Phabricator review in Meta.

[hannojg]

No, I did not yet (my main use case are automated tests on AWS device farm which on iOS/macOS runners only support ipv6 for connections)

[meta-codesync]

@cipolleschi merged this pull request in 4a59f90.

[react-native-bot]

This pull request was successfully merged by @hannojg in 4a59f90

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