fix: 修复更新弹窗无响应、内存泄漏、SQL注入、文件句柄泄漏及并发安全问题；优化导出功能

electron/utils/LRUCache.ts

@@ -0,0 +1,93 @@
+/**
+ * LRU (Least Recently Used) Cache implementation for memory management
+ */
+export class LRUCache<K, V> {
+  private cache: Map<K, V>
+  private maxSize: number
+
+  constructor(maxSize: number = 100) {
+    this.maxSize = maxSize
+    this.cache = new Map()
+  }
+
+  /**
+   * Get value from cache
+   */
+  get(key: K): V | undefined {
+    const value = this.cache.get(key)
+    if (value !== undefined) {
+      // Move to end (most recently used)
+      this.cache.delete(key)
+      this.cache.set(key, value)
+    }
+    return value
+  }
+
+  /**
+   * Set value in cache
+   */
+  set(key: K, value: V): void {
+    if (this.cache.has(key)) {
+      // Update existing
+      this.cache.delete(key)
+    } else if (this.cache.size >= this.maxSize) {
+      // Remove least recently used (first item)
+      const firstKey = this.cache.keys().next().value
+      if (firstKey !== undefined) {
+        this.cache.delete(firstKey)
+      }
+    }
+    this.cache.set(key, value)
+  }
+
+  /**
+   * Check if key exists
+   */
+  has(key: K): boolean {
+    return this.cache.has(key)
+  }
+
+  /**
+   * Delete key from cache
+   */
+  delete(key: K): boolean {
+    return this.cache.delete(key)
+  }
+
+  /**
+   * Clear all cache entries
+   */
+  clear(): void {
+    this.cache.clear()
+  }
+
+  /**
+   * Get current cache size
+   */
+  get size(): number {
+    return this.cache.size
+  }
+
+  /**
+   * Get all keys (for debugging)
+   */
+  keys(): IterableIterator<K> {
+    return this.cache.keys()
+  }
+
+  /**
+   * Force cleanup (optional method for explicit memory management)
+   */
+  cleanup(): void {
+    // In JavaScript/TypeScript, this is mainly for consistency
+    // The garbage collector will handle actual memory cleanup
+    if (this.cache.size > this.maxSize * 1.5) {
+      // Emergency cleanup if cache somehow exceeds limit
+      const entries = Array.from(this.cache.entries())
+      this.cache.clear()
+      // Keep only the most recent half
+      const keepEntries = entries.slice(-Math.floor(this.maxSize / 2))
+      keepEntries.forEach(([key, value]) => this.cache.set(key, value))
+    }
+  }
+}