新增车辆表及OTA权限与逻辑优化

新增车辆任务与报警表，完善实体与DbContext配置。细化OTA权限校验，增强回传会话IP安全。优化OTA上传与设置面板，调度器支持重启恢复。报警采集逻辑支持历史分段。

MiGu.Server/Ota/OtaStore.cs

@@ -24,6 +24,8 @@ public sealed class OtaStore
     private string? _lastPullId;
     private readonly System.Collections.Concurrent.ConcurrentDictionary<string, string> _pullByIp =
         new(StringComparer.OrdinalIgnoreCase);
+    private readonly System.Collections.Concurrent.ConcurrentDictionary<string, DateTime> _pullLastReceiveUtc =
+        new(StringComparer.OrdinalIgnoreCase);
     private long _jobSeq;
 
     public OtaStore(IWebHostEnvironment env, IOptions<OtaOptions> options, ILogger<OtaStore> log)
@@ -144,29 +146,44 @@ public sealed class OtaStore
         lock (_gate)
         {
             var ip = NormalizeIp(sourceIp);
+            // 必须匹配会话 IP；禁止无 IP 时回退到最近一次拉包（可被伪造/误写）。
             if (ip != null && _pullByIp.TryGetValue(ip, out var byIp))
             {
                 id = byIp;
                 return true;
             }
 
-            if (ip == null && _lastPullId != null)
-            {
-                id = _lastPullId;
-                return true;
-            }
-
             id = null;
             return false;
         }
     }
 
+    public void NotePullReceive(string? sourceIp)
+    {
+        var ip = NormalizeIp(sourceIp);
+        if (ip == null) return;
+        _pullLastReceiveUtc[ip] = DateTime.UtcNow;
+    }
+
+    public bool TryGetLastReceiveAt(string? sourceIp, out DateTime utc)
+    {
+        var ip = NormalizeIp(sourceIp);
+        if (ip != null && _pullLastReceiveUtc.TryGetValue(ip, out utc))
+            return true;
+        utc = default;
+        return false;
+    }
+
     public void ClearActivePull(string? sourceIp = null)
     {
         lock (_gate)
         {
             var ip = NormalizeIp(sourceIp);
-            if (ip != null) _pullByIp.TryRemove(ip, out _);
+            if (ip != null)
+            {
+                _pullByIp.TryRemove(ip, out _);
+                _pullLastReceiveUtc.TryRemove(ip, out _);
+            }
             if (_pullByIp.IsEmpty) _lastPullId = null;
         }
     }