⚡️ perf(frontend): 优化长时运行下的搜索与缓存占用

- 为 V2 cmd+k 搜索预建索引并限制初始/宽泛结果数量
- 清理冷数据库树和 DataViewer 长生命周期快照缓存
- 收紧运行时 SQL 日志预算并在 hydration 时压缩旧缓存

frontend/src/components/sidebarV2Utils.command-search.test.ts

@@ -0,0 +1,116 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  V2_COMMAND_SEARCH_INITIAL_TREE_LIMIT,
+  V2_COMMAND_SEARCH_MAX_TREE_RESULTS,
+  buildV2CommandSearchTreeIndex,
+  filterV2CommandSearchTreeItems,
+  parseV2CommandSearchQuery,
+  resolveSidebarDatabaseTreePruneKeys,
+  type V2CommandSearchItem,
+} from './sidebarV2Utils';
+
+const buildNodeItems = (count: number): V2CommandSearchItem[] => {
+  return Array.from({ length: count }, (_, index) => ({
+    key: `node-table-${index}`,
+    kind: 'node' as const,
+    title: `fs_order_${index}`,
+    meta: `开发240 · front_end_sys_${index % 4}`,
+    icon: null,
+    node: {
+      type: index % 6 === 0 ? 'view' : 'table',
+      key: `table-${index}`,
+      title: `fs_order_${index}`,
+      dataRef: {
+        tableName: `fs_order_${index}`,
+        viewName: index % 6 === 0 ? `v_order_${index}` : undefined,
+        dbName: `front_end_sys_${index % 4}`,
+        name: `obj_${index}`,
+        config: {
+          host: `10.0.0.${index % 16}`,
+        },
+      },
+    },
+  }));
+};
+
+describe('sidebarV2 command search performance helpers', () => {
+  it('keeps the initial tree result limit when the query is empty', () => {
+    const items = buildNodeItems(V2_COMMAND_SEARCH_INITIAL_TREE_LIMIT + 80);
+
+    expect(
+      filterV2CommandSearchTreeItems(items, parseV2CommandSearchQuery('')),
+    ).toHaveLength(V2_COMMAND_SEARCH_INITIAL_TREE_LIMIT);
+  });
+
+  it('caps broad keyword matches to avoid rendering the full loaded tree', () => {
+    const items = buildNodeItems(V2_COMMAND_SEARCH_MAX_TREE_RESULTS + 160);
+
+    const result = filterV2CommandSearchTreeItems(
+      items,
+      parseV2CommandSearchQuery('fs_order'),
+    );
+
+    expect(result).toHaveLength(V2_COMMAND_SEARCH_MAX_TREE_RESULTS);
+    expect(result[0]?.key).toBe('node-table-0');
+    expect(result[result.length - 1]?.key).toBe(`node-table-${V2_COMMAND_SEARCH_MAX_TREE_RESULTS - 1}`);
+  });
+
+  it('returns the same matches when filtering with a prebuilt search index', () => {
+    const items = buildNodeItems(200);
+    const index = buildV2CommandSearchTreeIndex(items);
+    const query = parseV2CommandSearchQuery('@fs_order_1');
+
+    expect(filterV2CommandSearchTreeItems(index, query)).toEqual(
+      filterV2CommandSearchTreeItems(items, query),
+    );
+  });
+
+  it('prunes only cold collapsed database trees when too many object trees stay loaded', () => {
+    expect(resolveSidebarDatabaseTreePruneKeys({
+      treeData: [
+        {
+          key: 'conn-1',
+          title: 'conn-1',
+          type: 'connection',
+          children: [
+            {
+              key: 'conn-1-db-a',
+              title: 'db-a',
+              type: 'database',
+              children: [{ key: 'a-tables', title: '表', type: 'object-group' }],
+            },
+            {
+              key: 'conn-1-db-b',
+              title: 'db-b',
+              type: 'database',
+              children: [{ key: 'b-tables', title: '表', type: 'object-group' }],
+            },
+            {
+              key: 'conn-1-db-c',
+              title: 'db-c',
+              type: 'database',
+              children: [{ key: 'c-tables', title: '表', type: 'object-group' }],
+            },
+            {
+              key: 'conn-1-db-d',
+              title: 'db-d',
+              type: 'database',
+              children: [{ key: 'd-tables', title: '表', type: 'object-group' }],
+            },
+          ],
+        },
+      ],
+      expandedKeys: ['conn-1-db-c'],
+      selectedKeys: [],
+      activeDatabaseKey: 'conn-1-db-d',
+      touchedAtByDatabaseKey: {
+        'conn-1-db-a': 10,
+        'conn-1-db-b': 20,
+        'conn-1-db-c': 30,
+        'conn-1-db-d': 40,
+      },
+      maxLoadedDatabases: 2,
+    })).toEqual(['conn-1-db-a', 'conn-1-db-b']);
+  });
+});