Two issues found during M8 E2E testing on Forgejo:
1. CI test failures (31 tests): Unit tests assume GitHub context but
Forgejo runner sets GITHUB_SERVER_URL=git.wxs.ro, causing
detectPlatform() to return "forgejo" and module-level constants in
config.ts to use Forgejo URLs. Fixed by setting GITHUB_SERVER_URL
in the test step env. Forgejo-specific tests already override with
PLATFORM=forgejo in their beforeEach.
2. Permission check 403: Forgejo's getCollaboratorPermissionLevel
requires admin access. Added checkForgejoPermissions() that uses
GET /repos/{owner}/{repo} instead — returns a permissions object
with { admin, push, pull } booleans for the authenticated token.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
