feat(updates): check Gitea automatically and deploy on owner confirmation

Add owner-only update controls, a read-only SSH checker and independent systemd deployment services. Build before maintenance; back up code and database; restore on failed deployment. Preserve runtime configuration and gate business writes during the switch.

deploy/server/updater/state.py

@@ -0,0 +1,70 @@
+"""Persistent state shared by the independent update services."""
+from __future__ import annotations
+
+import fcntl
+import json
+import os
+from contextlib import contextmanager
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Any, Iterator
+
+CONFIG_FILE = Path('/etc/replypier-updater/config.json')
+BUSY = {'queued', 'preparing', 'building', 'backing_up', 'deploying', 'migrating', 'verifying', 'rolling_back'}
+
+
+def now() -> str:
+    return datetime.now(timezone.utc).isoformat()
+
+
+def config() -> dict[str, Any]:
+    return json.loads(CONFIG_FILE.read_text())
+
+
+def directory(cfg: dict[str, Any]) -> Path:
+    return Path(cfg['state_dir'])
+
+
+def read(cfg: dict[str, Any]) -> dict[str, Any]:
+    p = directory(cfg) / 'status.json'
+    return json.loads(p.read_text()) if p.exists() else {
+        'current': {'revision': cfg['initial_revision'], 'subject': '已安装版本'},
+        'latest': None, 'checked_at': None, 'checking': False,
+        'check_error': None, 'update': {'status': 'idle', 'message': ''},
+    }
+
+
+def write(cfg: dict[str, Any], state: dict[str, Any]) -> None:
+    target = directory(cfg) / 'status.json'
+    temp = target.with_suffix('.tmp')
+    with temp.open('w') as out:
+        json.dump(state, out, ensure_ascii=False, indent=2)
+        out.flush()
+        os.fsync(out.fileno())
+    temp.chmod(0o644)
+    temp.replace(target)
+
+
+@contextmanager
+def transaction(cfg: dict[str, Any]) -> Iterator[dict[str, Any]]:
+    directory(cfg).mkdir(parents=True, exist_ok=True)
+    with (directory(cfg) / 'state.lock').open('a') as lock:
+        fcntl.flock(lock, fcntl.LOCK_EX)
+        state = read(cfg)
+        yield state
+        write(cfg, state)
+
+
+def progress(cfg: dict[str, Any], status: str, message: str, **values: Any) -> None:
+    with transaction(cfg) as state:
+        state['update'].update(status=status, message=message, **values)
+
+
+def public_status(cfg: dict[str, Any]) -> dict[str, Any]:
+    state = read(cfg)
+    current = state['current']['revision']
+    latest = (state.get('latest') or {}).get('revision')
+    return {**state, 'configured': True, 'can_manage': True,
+            'repository_url': cfg['web_url'], 'branch': cfg['branch'],
+            'check_interval_minutes': 30,
+            'update_available': bool(latest and latest != current and not state.get('check_error'))}