Rebrand the built-in actions bot user from upstream Gitea naming to
MokoGitea branding:
- Name: gitea-actions → mokogitea-actions
- FullName: Gitea Actions → MokoGitea Actions
- Email: teabot@gitea.io → mokogitea-actions[bot]@mokoconsulting.tech
Add backward-compatible name recognition so all three bot name variants
(mokogitea-actions, gitea-actions, github-actions) with optional [bot]
suffix resolve to the same system user.
Add WhitelistActionsUser, MergeWhitelistActionsUser, and
ForcePushAllowlistActionsUser toggles to branch protection rules,
allowing CI/CD workflows to push to protected branches when explicitly
enabled. Previously the actions bot (virtual user ID -2) could never be
added to whitelist because updateUserWhitelist() only validates real
database users.
Closes#233
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>