fix: db.get_or_404 -> query.get_or_404 + rename to Palladium Monitor

- 修复删除快照时 AttributeError: SQLAlchemy.get_or_404 (低版本兼容)
- UI/标题/邮件主题从 'Palladium Z1 Monitor' 改为 'Palladium Monitor'

app.py

@@ -1,9 +1,9 @@
 from typing import List, Dict, Tuple, Set, Any, Optional, Union
 #!/usr/bin/env python3
 """
-Palladium Z1 Monitor — LD逻辑板使用监控系统
+Palladium Monitor — LD逻辑板使用监控系统
 
-解析 `test_server -short` 输出，展示 Palladium Z1 仿真器的
+解析 `test_server -short` 输出，展示 Palladium 仿真器的
 逻辑板 (LD) 状态、逻辑板利用率、作业信息和 T-Pod 可用性。
 
 支持两种数据来源:
@@ -520,7 +520,7 @@ def history():
 @app.route("/snapshot/<int:sid>")
 def snapshot_detail(sid):
     """单条快照详情。"""
-    snapshot = db.get_or_404(ScanSnapshot, sid)
+    snapshot = ScanSnapshot.query.get_or_404(sid)
     stats = {
         "total_boards": snapshot.total_boards,
         "online_boards": snapshot.online_boards,
@@ -681,7 +681,7 @@ def api_history():
 @app.route("/api/snapshot/<int:sid>/delete", methods=["POST"])
 def delete_snapshot(sid):
     """删除指定快照。"""
-    snapshot = db.get_or_404(ScanSnapshot, sid)
+    snapshot = ScanSnapshot.query.get_or_404(sid)
     db.session.delete(snapshot)
     db.session.commit()
     return redirect(url_for("history"))
@@ -1270,7 +1270,7 @@ if __name__ == "__main__":
         seed_sample_data()
     start_email_scheduler()
     print("════════════════════════════════════════════════════════")
-    print("  Palladium Z1 Monitor")
+    print("  Palladium Monitor")
     print("  http://0.0.0.0:5100")
     print("════════════════════════════════════════════════════════")
     app.run(host="0.0.0.0", port=5100, debug=True)