* chore(ci): use OpenCode app credentials for fixer PRs
Mint GitHub App tokens for ci-fixer and issue-fixer so opened PRs
trigger CI and can be auto-merged, matching the opencode repo pattern.
* chore(ci): app credentials for ci-fixer and model sync only
Keep issue-fixer on GITHUB_TOKEN. Use the OpenCode app for ci-fixer
and sync-models so their PRs trigger CI.
* fix(ci): keep GITHUB_TOKEN for sync issue creation
Missing-model issues must be opened with GITHUB_TOKEN so issues.opened
does not fire; Issue Fixer is started only via repository_dispatch.
Use the app token only when reporting/pushing catalog PRs.
Aiden Cline