Add admin/user roles, /edit command, sticker support, and registry push workflow

- Split docker-compose into build (docker-compose.build.yaml) and deploy (docker-compose.yaml pulls from registry)
- Add push.sh for building and pushing versioned images to git.goyban.com/goyban/bot_meme
- Add ADMIN_USERS env var; admins can add/edit/delete, users can search
- Add /edit command with inline keyboard to update meme keywords
- Add sticker support (save and serve via inline)
- Switch /delete to use numeric row ID instead of file_unique_id
- Search is now global (shared pool) instead of per-user

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -2,3 +2,4 @@
 bot_db/
 __pycache__/
 *.pyc
+push.sh