测试版本，添加了模拟好友并优化了本地缓存

electron/services/messageCacheService.ts

@@ -0,0 +1,68 @@
+import { join, dirname } from 'path'
+import { existsSync, mkdirSync, readFileSync, writeFileSync } from 'fs'
+import { app } from 'electron'
+
+export interface SessionMessageCacheEntry {
+  updatedAt: number
+  messages: any[]
+}
+
+export class MessageCacheService {
+  private readonly cacheFilePath: string
+  private cache: Record<string, SessionMessageCacheEntry> = {}
+  private readonly sessionLimit = 150
+
+  constructor(cacheBasePath?: string) {
+    const basePath = cacheBasePath && cacheBasePath.trim().length > 0
+      ? cacheBasePath
+      : join(app.getPath('userData'), 'WeFlowCache')
+    this.cacheFilePath = join(basePath, 'session-messages.json')
+    this.ensureCacheDir()
+    this.loadCache()
+  }
+
+  private ensureCacheDir() {
+    const dir = dirname(this.cacheFilePath)
+    if (!existsSync(dir)) {
+      mkdirSync(dir, { recursive: true })
+    }
+  }
+
+  private loadCache() {
+    if (!existsSync(this.cacheFilePath)) return
+    try {
+      const raw = readFileSync(this.cacheFilePath, 'utf8')
+      const parsed = JSON.parse(raw)
+      if (parsed && typeof parsed === 'object') {
+        this.cache = parsed
+      }
+    } catch (error) {
+      console.error('MessageCacheService: 载入缓存失败', error)
+      this.cache = {}
+    }
+  }
+
+  get(sessionId: string): SessionMessageCacheEntry | undefined {
+    return this.cache[sessionId]
+  }
+
+  set(sessionId: string, messages: any[]): void {
+    if (!sessionId) return
+    const trimmed = messages.length > this.sessionLimit
+      ? messages.slice(-this.sessionLimit)
+      : messages.slice()
+    this.cache[sessionId] = {
+      updatedAt: Date.now(),
+      messages: trimmed
+    }
+    this.persist()
+  }
+
+  private persist() {
+    try {
+      writeFileSync(this.cacheFilePath, JSON.stringify(this.cache), 'utf8')
+    } catch (error) {
+      console.error('MessageCacheService: 保存缓存失败', error)
+    }
+  }
+}