fix(init): Fix yarn + skip-install combo causing template copy failure

[azizbecha]

Summary

This PR fixes a bug where specifying --pm yarn together with --skip-install caused the init command to fail during template copying. The issue occurred because yarn configuration commands were not being awaited before installing the template package, creating a race condition where node_modules wasn't fully created before template copying attempted to access template.config.js.

closes #2743

Additionally, this PR fixes an issue where require.resolve('react-native') was being called even when --install-pods false, causing failures with custom templates that don't include react-native.

Reproducible demo:

npx @react-native-community/cli@latest init RN0821Test3 --skip-install --pm yarn

Error before fix:

error Couldn't find the "/var/folders/.../node_modules/@react-native-community/template/template.config.js file inside "@react-native-community/template" template.

Test Plan

1. Added e2e test: Created init supports --pm yarn together with --skip-install test case that verifies the combination works correctly

2. Updated test expectations: Modified test to account for Yarn 2+ configuration files (.yarn, .yarnrc.yml) that are created when using yarn

3. Manual verification: Tested the exact command from the bug report:

   npx @react-native-community/cli@latest init RN0821Test3 --skip-install --pm yarn

   This now completes successfully without errors.

4. Regression testing: Verified that:

   • --pm yarn without --skip-install still works
   • --pm npm with --skip-install still works
   • --pm bun with --skip-install still works
   • Custom templates with --install-pods false no longer fail with react-native resolution errors

Changes made:

• packages/cli/src/commands/init/template.ts: Added await to yarn config executeCommand calls to ensure they complete before template installation
• packages/cli/src/commands/init/init.ts: Moved require.resolve('react-native') inside conditional blocks so it only runs when CocoaPods installation is requested
• __e2e__/init.test.ts: Added test case and updated file expectations for Yarn 2+ config files

Checklist

• Documentation is up to date.
• Follows commit message convention described in CONTRIBUTING.md.
• For functional changes, my test plan has linked these CLI changes into a local react-native checkout (instructions).