feat: add backup CLI commands, AI correction/modifier services, and timezone-aware date display

- Add `devplace backups` CLI subcommands (list, run, prune, clear) with job enqueueing and orphan cleanup
- Introduce `BACKUPS_DIR` and `BACKUP_STAGING_DIR` config paths for backup storage
- Implement `schedule_correction` and `schedule_modification` calls in content creation, comment creation, and comment editing flows
- Add `DEFAULT_CORRECTION_PROMPT` and `DEFAULT_MODIFIER_PROMPT` config constants for AI content processing
- Document timezone-aware date display using `local_dt`/`dt_ago` Jinja globals with client-side `Intl` localization
- Update README with AI content correction/modifier support in direct messages via `@ai` inline instructions
- Add `track_action(user["uid"], "vote")` call on upvote in `apply_vote`

devplacepy/routers/admin/__init__.py

@@ -4,6 +4,7 @@ from devplacepy.routers.admin import (
     aiquota,
     aiusage,
     auditlog,
+    backups,
     bots,
     containers,
     issues,
@@ -27,6 +28,7 @@ router.include_router(notifications.router)
 router.include_router(news.router)
 router.include_router(issues.router)
 router.include_router(auditlog.router)
+router.include_router(backups.router)
 router.include_router(bots.router)
 router.include_router(services.router, prefix="/services")
 router.include_router(containers.router, prefix="/containers")