feat(migration): enable silent JSON to SQLite migration with toast notification

- Remove environment variable feature gate (CC_SWITCH_ENABLE_JSON_DB_MIGRATION)
- Automatically migrate config.json to SQLite when db doesn't exist
- Archive migrated config.json as config.json.migrated for recovery
- Add migration success flag in init_status.rs (one-time consumption)
- Add get_migration_result command for frontend to query
- Show toast notification on successful migration in App.tsx

src-tauri/src/commands/misc.rs

@@ -51,3 +51,10 @@ pub async fn is_portable_mode() -> Result<bool, String> {
 pub async fn get_init_error() -> Result<Option<InitErrorPayload>, String> {
     Ok(crate::init_status::get_init_error())
 }
+
+/// 获取 JSON→SQLite 迁移结果（若有）。
+/// 只返回一次 true，之后返回 false，用于前端显示一次性 Toast 通知。
+#[tauri::command]
+pub async fn get_migration_result() -> Result<bool, String> {
+    Ok(crate::init_status::take_migration_success())
+}

src-tauri/src/init_status.rs

@@ -25,6 +25,33 @@ pub fn get_init_error() -> Option<InitErrorPayload> {
     cell().read().ok()?.clone()
 }
 
+// ============================================================
+// 迁移结果状态
+// ============================================================
+
+static MIGRATION_SUCCESS: OnceLock<RwLock<bool>> = OnceLock::new();
+
+fn migration_cell() -> &'static RwLock<bool> {
+    MIGRATION_SUCCESS.get_or_init(|| RwLock::new(false))
+}
+
+pub fn set_migration_success() {
+    if let Ok(mut guard) = migration_cell().write() {
+        *guard = true;
+    }
+}
+
+/// 获取并消费迁移成功状态（只返回一次 true，之后返回 false）
+pub fn take_migration_success() -> bool {
+    if let Ok(mut guard) = migration_cell().write() {
+        let val = *guard;
+        *guard = false;
+        val
+    } else {
+        false
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src-tauri/src/lib.rs

@@ -113,25 +113,6 @@ const TRAY_SECTIONS: [TrayAppSection; 3] = [
     },
 ];
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-enum JsonMigrationMode {
-    Disabled,
-    DryRun,
-    Enabled,
-}
-
-/// 解析 JSON→DB 迁移模式：默认关闭，支持 dryrun/模拟演练
-fn json_migration_mode() -> JsonMigrationMode {
-    match std::env::var("CC_SWITCH_ENABLE_JSON_DB_MIGRATION") {
-        Ok(val) => match val.trim().to_ascii_lowercase().as_str() {
-            "1" | "true" | "yes" | "on" => JsonMigrationMode::Enabled,
-            "dryrun" | "dry-run" | "simulate" | "sim" => JsonMigrationMode::DryRun,
-            _ => JsonMigrationMode::Disabled,
-        },
-        Err(_) => JsonMigrationMode::Disabled,
-    }
-}
-
 fn append_provider_section<'a>(
     app: &'a tauri::AppHandle,
     mut menu_builder: MenuBuilder<'a, tauri::Wry, tauri::AppHandle<tauri::Wry>>,
@@ -561,8 +542,7 @@ pub fn run() {
             let db_path = app_config_dir.join("cc-switch.db");
             let json_path = app_config_dir.join("config.json");
 
-            // Check if config.json→SQLite migration needed (feature gated, disabled by default)
-            let migration_mode = json_migration_mode();
+            // 检查是否需要从 config.json 迁移到 SQLite
             let has_json = json_path.exists();
             let has_db = db_path.exists();
 
@@ -576,42 +556,27 @@ pub fn run() {
                 }
             };
 
+            // 静默迁移：检测到旧版 config.json 且数据库不存在时自动迁移
             if !has_db && has_json {
-                match migration_mode {
-                    JsonMigrationMode::Disabled => {
-                        log::warn!(
-                            "Detected config.json but migration is disabled by default. \
-                             Set CC_SWITCH_ENABLE_JSON_DB_MIGRATION=1 to migrate, or =dryrun to validate first."
-                        );
-                    }
-                    JsonMigrationMode::DryRun => {
-                        log::info!("Running migration dry-run (validation only, no disk writes)");
-                        match crate::app_config::MultiAppConfig::load() {
-                            Ok(config) => {
-                                if let Err(e) = crate::database::Database::migrate_from_json_dry_run(&config) {
-                                    log::error!("Migration dry-run failed: {e}");
-                                } else {
-                                    log::info!("Migration dry-run succeeded (no database written)");
-                                }
+                log::info!("检测到旧版配置文件，开始自动迁移到数据库...");
+                match crate::app_config::MultiAppConfig::load() {
+                    Ok(config) => {
+                        if let Err(e) = db.migrate_from_json(&config) {
+                            log::error!("配置迁移失败: {e}，将从现有配置导入");
+                        } else {
+                            log::info!("✓ 配置迁移成功");
+                            // 标记迁移成功，供前端显示 Toast
+                            crate::init_status::set_migration_success();
+                            // 归档旧配置文件（重命名而非删除，便于用户恢复）
+                            let archive_path = json_path.with_extension("json.migrated");
+                            if let Err(e) = std::fs::rename(&json_path, &archive_path) {
+                                log::warn!("归档旧配置文件失败: {e}");
+                            } else {
+                                log::info!("✓ 旧配置已归档为 config.json.migrated");
                             }
-                            Err(e) => log::error!("Failed to load config.json for dry-run: {e}"),
-                        }
-                    }
-                    JsonMigrationMode::Enabled => {
-                        log::info!("Starting migration from config.json to SQLite (user opt-in)");
-                        match crate::app_config::MultiAppConfig::load() {
-                            Ok(config) => {
-                                if let Err(e) = db.migrate_from_json(&config) {
-                                    log::error!("Migration failed: {e}");
-                                } else {
-                                    log::info!("Migration successful");
-                                    // Optional: Rename config.json to prevent re-migration
-                                    // let _ = std::fs::rename(&json_path, json_path.with_extension("json.migrated"));
-                                }
-                            }
-                            Err(e) => log::error!("Failed to load config.json for migration: {e}"),
                         }
                     }
+                    Err(e) => log::error!("加载旧配置文件失败: {e}，将从现有配置导入"),
                 }
             }
 
@@ -822,6 +787,7 @@ pub fn run() {
             commands::pick_directory,
             commands::open_external,
             commands::get_init_error,
+            commands::get_migration_result,
             commands::get_app_config_path,
             commands::open_app_config_folder,
             commands::get_claude_common_config_snippet,

src/App.tsx

@@ -1,6 +1,7 @@
 import { useEffect, useMemo, useState, useRef } from "react";
 import { useTranslation } from "react-i18next";
 import { toast } from "sonner";
+import { invoke } from "@tauri-apps/api/core";
 import {
   Plus,
   Settings,
@@ -123,6 +124,24 @@ function App() {
     checkEnvOnStartup();
   }, []);
 
+  // 应用启动时检查是否刚完成了配置迁移
+  useEffect(() => {
+    const checkMigration = async () => {
+      try {
+        const migrated = await invoke<boolean>("get_migration_result");
+        if (migrated) {
+          toast.success(
+            t("migration.success", { defaultValue: "配置迁移成功" }),
+          );
+        }
+      } catch (error) {
+        console.error("[App] Failed to check migration result:", error);
+      }
+    };
+
+    checkMigration();
+  }, [t]);
+
   // 切换应用时检测当前应用的环境变量冲突
   useEffect(() => {
     const checkEnvOnSwitch = async () => {