feat: M5 外观特效选择+持久化（appearance:load/save IPC+config.json，鼠效 6 选格接 EffectEngine，重开恢复并接线）

apps/desktop/src/main/services/config-store.ts

@@ -6,13 +6,13 @@ import { RECENT_VAULT_MAX } from '@hunter/shared';
 
 export class ConfigStore {
   private file: string;
-  private cache: { vault?: VaultMeta } | null = null;
+  private cache: { vault?: VaultMeta; appearance?: { themeId: string; params: Record<string, unknown>; effect: string } } | null = null;
 
   constructor(userDataDir: string) {
     this.file = nodePath.join(userDataDir, 'config.json');
   }
 
-  private async read(): Promise<{ vault?: VaultMeta }> {
+  private async read(): Promise<{ vault?: VaultMeta; appearance?: { themeId: string; params: Record<string, unknown>; effect: string } }> {
     if (this.cache) return this.cache;
     try {
       const raw = await fs.readFile(this.file, 'utf8');
@@ -46,6 +46,15 @@ export class ConfigStore {
     return meta;
   }
 
+  async getAppearance(): Promise<{ themeId: string; params: Record<string, unknown>; effect: string } | null> {
+    const c = await this.read();
+    return c.appearance ?? null;
+  }
+  async saveAppearance(data: { themeId: string; params: Record<string, unknown>; effect: string }): Promise<void> {
+    (await this.read()).appearance = data;
+    await this.write();
+  }
+
   async setDefaultRoot(root: string): Promise<VaultMeta> {
     const meta = await this.getVaultMeta();
     meta.defaultRoot = root;