feat: migrate Claude common config snippet from localStorage to config.json

Migrate the Claude common config snippet storage from browser localStorage
to the persistent config.json file for better cross-device sync and backup support.

**Backend Changes:**
- Add `claude_common_config_snippet` field to `MultiAppConfig` struct
- Add `get_claude_common_config_snippet` and `set_claude_common_config_snippet` Tauri commands
- Include JSON validation in the setter command

**Frontend Changes:**
- Create new `lib/api/config.ts` API module
- Refactor `useCommonConfigSnippet` hook to use config.json instead of localStorage
- Add automatic one-time migration from localStorage to config.json
- Add loading state during initialization

**Benefits:**
- Cross-device synchronization via backup/restore
- More reliable persistence than browser storage
- Centralized configuration management
- Seamless migration for existing users

src/components/providers/forms/hooks/useCommonConfigSnippet.ts

@@ -4,8 +4,9 @@ import {
   hasCommonConfigSnippet,
   validateJsonConfig,
 } from "@/utils/providerConfigUtils";
+import { configApi } from "@/lib/api";
 
-const COMMON_CONFIG_STORAGE_KEY = "cc-switch:common-config-snippet";
+const LEGACY_STORAGE_KEY = "cc-switch:common-config-snippet";
 const DEFAULT_COMMON_CONFIG_SNIPPET = `{
   "includeCoAuthoredBy": false
 }`;
@@ -20,6 +21,7 @@ interface UseCommonConfigSnippetProps {
 
 /**
  * 管理 Claude 通用配置片段
+ * 从 config.json 读取和保存，支持从 localStorage 平滑迁移
  */
 export function useCommonConfigSnippet({
   settingsConfig,
@@ -27,30 +29,67 @@ export function useCommonConfigSnippet({
   initialData,
 }: UseCommonConfigSnippetProps) {
   const [useCommonConfig, setUseCommonConfig] = useState(false);
-  const [commonConfigSnippet, setCommonConfigSnippetState] = useState<string>(
-    () => {
-      if (typeof window === "undefined") {
-        return DEFAULT_COMMON_CONFIG_SNIPPET;
-      }
-      try {
-        const stored = window.localStorage.getItem(COMMON_CONFIG_STORAGE_KEY);
-        if (stored && stored.trim()) {
-          return stored;
-        }
-      } catch {
-        // ignore localStorage 读取失败
-      }
-      return DEFAULT_COMMON_CONFIG_SNIPPET;
-    },
-  );
+  const [commonConfigSnippet, setCommonConfigSnippetState] =
+    useState<string>(DEFAULT_COMMON_CONFIG_SNIPPET);
   const [commonConfigError, setCommonConfigError] = useState("");
+  const [isLoading, setIsLoading] = useState(true);
 
   // 用于跟踪是否正在通过通用配置更新
   const isUpdatingFromCommonConfig = useRef(false);
 
+  // 初始化：从 config.json 加载，支持从 localStorage 迁移
+  useEffect(() => {
+    let mounted = true;
+
+    const loadSnippet = async () => {
+      try {
+        // 尝试从 config.json 加载
+        const snippet = await configApi.getClaudeCommonConfigSnippet();
+
+        if (snippet && snippet.trim()) {
+          if (mounted) {
+            setCommonConfigSnippetState(snippet);
+          }
+        } else {
+          // 如果 config.json 中没有，尝试从 localStorage 迁移
+          if (typeof window !== "undefined") {
+            try {
+              const legacySnippet =
+                window.localStorage.getItem(LEGACY_STORAGE_KEY);
+              if (legacySnippet && legacySnippet.trim()) {
+                // 迁移到 config.json
+                await configApi.setClaudeCommonConfigSnippet(legacySnippet);
+                if (mounted) {
+                  setCommonConfigSnippetState(legacySnippet);
+                }
+                // 清理 localStorage
+                window.localStorage.removeItem(LEGACY_STORAGE_KEY);
+                console.log("[迁移] 通用配置已从 localStorage 迁移到 config.json");
+              }
+            } catch (e) {
+              console.warn("[迁移] 从 localStorage 迁移失败:", e);
+            }
+          }
+        }
+      } catch (error) {
+        console.error("加载通用配置失败:", error);
+      } finally {
+        if (mounted) {
+          setIsLoading(false);
+        }
+      }
+    };
+
+    loadSnippet();
+
+    return () => {
+      mounted = false;
+    };
+  }, []);
+
   // 初始化时检查通用配置片段（编辑模式）
   useEffect(() => {
-    if (initialData) {
+    if (initialData && !isLoading) {
       const configString = JSON.stringify(initialData.settingsConfig, null, 2);
       const hasCommon = hasCommonConfigSnippet(
         configString,
@@ -58,24 +97,7 @@ export function useCommonConfigSnippet({
       );
       setUseCommonConfig(hasCommon);
     }
-  }, [initialData, commonConfigSnippet]);
-
-  // 同步本地存储的通用配置片段
-  useEffect(() => {
-    if (typeof window === "undefined") return;
-    try {
-      if (commonConfigSnippet.trim()) {
-        window.localStorage.setItem(
-          COMMON_CONFIG_STORAGE_KEY,
-          commonConfigSnippet,
-        );
-      } else {
-        window.localStorage.removeItem(COMMON_CONFIG_STORAGE_KEY);
-      }
-    } catch {
-      // ignore
-    }
-  }, [commonConfigSnippet]);
+  }, [initialData, commonConfigSnippet, isLoading]);
 
   // 处理通用配置开关
   const handleCommonConfigToggle = useCallback(
@@ -113,6 +135,11 @@ export function useCommonConfigSnippet({
 
       if (!value.trim()) {
         setCommonConfigError("");
+        // 保存到 config.json（清空）
+        configApi.setClaudeCommonConfigSnippet("").catch((error) => {
+          console.error("保存通用配置失败:", error);
+        });
+
         if (useCommonConfig) {
           const { updatedConfig } = updateCommonConfigSnippet(
             settingsConfig,
@@ -131,6 +158,11 @@ export function useCommonConfigSnippet({
         setCommonConfigError(validationError);
       } else {
         setCommonConfigError("");
+        // 保存到 config.json
+        configApi.setClaudeCommonConfigSnippet(value).catch((error) => {
+          console.error("保存通用配置失败:", error);
+          setCommonConfigError(`保存失败: ${error}`);
+        });
       }
 
       // 若当前启用通用配置且格式正确，需要替换为最新片段
@@ -169,7 +201,7 @@ export function useCommonConfigSnippet({
 
   // 当配置变化时检查是否包含通用配置（但避免在通过通用配置更新时检查）
   useEffect(() => {
-    if (isUpdatingFromCommonConfig.current) {
+    if (isUpdatingFromCommonConfig.current || isLoading) {
       return;
     }
     const hasCommon = hasCommonConfigSnippet(
@@ -177,12 +209,13 @@ export function useCommonConfigSnippet({
       commonConfigSnippet,
     );
     setUseCommonConfig(hasCommon);
-  }, [settingsConfig, commonConfigSnippet]);
+  }, [settingsConfig, commonConfigSnippet, isLoading]);
 
   return {
     useCommonConfig,
     commonConfigSnippet,
     commonConfigError,
+    isLoading,
     handleCommonConfigToggle,
     handleCommonConfigSnippetChange,
   };

src/lib/api/config.ts

@@ -0,0 +1,21 @@
+// 配置相关 API
+import { invoke } from "@tauri-apps/api/core";
+
+/**
+ * 获取 Claude 通用配置片段
+ * @returns 通用配置片段（JSON 字符串），如果不存在则返回 null
+ */
+export async function getClaudeCommonConfigSnippet(): Promise<string | null> {
+  return invoke<string | null>("get_claude_common_config_snippet");
+}
+
+/**
+ * 设置 Claude 通用配置片段
+ * @param snippet - 通用配置片段（JSON 字符串）
+ * @throws 如果 JSON 格式无效
+ */
+export async function setClaudeCommonConfigSnippet(
+  snippet: string,
+): Promise<void> {
+  return invoke("set_claude_common_config_snippet", { snippet });
+}

src/lib/api/index.ts

@@ -5,5 +5,6 @@ export { mcpApi } from "./mcp";
 export { promptsApi } from "./prompts";
 export { usageApi } from "./usage";
 export { vscodeApi } from "./vscode";
+export * as configApi from "./config";
 export type { ProviderSwitchEvent } from "./providers";
 export type { Prompt } from "./prompts";