refactor: 修复 any 滥用 & 拆分 tool-handlers.ts & 记忆数据治理 (v5.1.3)

Fix 2 - 类型安全:
- (window as any).metonaDesktop → window.metonaDesktop
- any[] → Record<string, unknown>[]
- 回调 :any → ChatSession | null
- 78 处 → 38 处（减少 51%）

Fix 3 - 架构拆分:
- tool-handlers.ts (1308行) → 4 个模块:
  - tool-handlers-shared.ts: 共享工具函数
  - tool-handlers-fs.ts: 15 个文件系统操作
  - tool-handlers-system.ts: 6 个系统网络操作
  - tool-handlers-git.ts: 1 个 Git 操作

Fix 4 - 记忆数据治理:
- 90 天未使用自动降低 importance
- 清理评分新增 agePenalty
- 向量错误日志增强（记忆ID、内容摘要、模型、栈）
- 去重增强（前缀匹配）

src/renderer/components/memory-modal.ts

@@ -152,8 +152,8 @@ export function initMemoryModal(): void {
   document.querySelector('#btnMemory')?.addEventListener('click', openMemoryModal);
 
   // 全局状态监听
-  if (typeof (window as any).__memoryStateListener === 'undefined') {
-    (window as any).__memoryStateListener = true;
+  if (typeof (window as unknown as { __memoryStateListener?: boolean }).__memoryStateListener === 'undefined') {
+    (window as unknown as { __memoryStateListener?: boolean }).__memoryStateListener = true;
     // 简单轮询：在模态框打开时监听变化
   }
 }
@@ -195,9 +195,9 @@ function updateVectorBadge(): void {
 
 function updateStats(): void {
   const entries = getMemoryCache();
-  const counts = { total: entries.length, fact: 0, preference: 0, rule: 0 };
+  const counts: Record<string, number> = { total: entries.length, fact: 0, preference: 0, rule: 0 };
   for (const e of entries) {
-    if (e.type in counts) (counts as any)[e.type]++;
+    if (e.type in counts) counts[e.type]++;
   }
   const el = (id: string) => modalEl.querySelector(`#${id}`)!;
   el('memStatTotal').textContent = String(counts.total);
@@ -295,7 +295,7 @@ async function importMemoryFromMd(): Promise<void> {
     return;
   }
 
-  const bridge = (window as any).metonaDesktop;
+  const bridge = window.metonaDesktop;
   if (!bridge || !bridge.isDesktop) {
     showToast('导入功能仅在桌面端可用', 'warning');
     return;