refactor(service): migrate auth, git service, agent from slog to tracing
- Remove all use slog::* imports and slog::Logger fields/parameters
- Replace slog::info!/warn!/error! with tracing::info!/warn!/error!
- AppService: remove pub logs: slog::Logger field, update callers of
AppEmail::init(), MessageProducer::new(), RoomService::new(),
start_email_worker(), start_room_workers()
- auth/: captcha, email, login, logout, password, register, rsa, totp
- git/: archive, blame, blob, branch, commit, contributors, diff,
refs, star, tag, tree, watch
- agent/: billing (ai_usage_recorded), code_review, pr_summary, sync
- project/activity.rs, workspace/alert.rs
773da34fab