fix(storage): retry a read transaction that fails to begin under load

server/src/WebDrop.Storage/SqliteChannelStore.cs

@@ -51,11 +51,21 @@ public sealed class SqliteChannelStore : IResourceStore, IDisposable
 
     public T Read<T>(Func<IResourceTx, T> action)
     {
-        using var conn = Open();
-        // 显式事务让一次 Read 内的多条查询看到同一份快照
-        // 读事务延迟到首次访问时才取快照，避免并发读预检抢占 SQLite 写锁。
-        using var tx = conn.BeginTransaction(deferred: true);
-        return action(new SqliteTx(conn));
+        for (int attempt = 0; ; attempt++)
+        {
+            using var conn = Open();
+            // 显式事务让一次 Read 内的多条查询看到同一份快照
+            // 读事务延迟到首次访问时才取快照，避免并发读预检抢占 SQLite 写锁。
+            SqliteTransaction tx;
+            try { tx = conn.BeginTransaction(deferred: true); }
+            // 并发压力下偶发 SQLITE_ERROR(CI 的并行追加测试里出现过):丢弃这条连接和池里的闲置连接,换新连接重试
+            catch (SqliteException e) when (e.SqliteErrorCode == 1 && attempt < 2)
+            {
+                SqliteConnection.ClearPool(conn);
+                continue;
+            }
+            using (tx) return action(new SqliteTx(conn));
+        }
     }
 
     public T Write<T>(Func<IResourceTx, T> action)