feat(provider): use live config for edit and backfill SSOT after switch

- Edit modal (Claude+Codex): when editing the current provider, initialize form from live files (Claude: ~/.claude/settings.json; Codex: ~/.codex/auth.json + ~/.codex/config.toml) instead of SSOT.
- Switch (Claude): after writing live settings.json for the target provider, read it back and update the provider’s SSOT to match live.
- Switch (Codex): keep MCP sync to config.toml, then read back TOML and update the target provider’s SSOT (preserves mcp.servers/mcp_servers schema).
- Add Tauri command read_live_provider_settings for both apps, register handler, and expose window.api.getLiveProviderSettings.
- Types updated accordingly; cargo check and pnpm typecheck pass.

src/vite-env.d.ts

@@ -96,6 +96,10 @@ declare global {
       syncEnabledMcpToCodex: () => Promise<boolean>;
       importMcpFromClaude: () => Promise<number>;
       importMcpFromCodex: () => Promise<number>;
+      // 读取当前生效（live）的 provider settings（根据 appType）
+      // Codex: { auth: object, config: string }
+      // Claude: settings.json 内容
+      getLiveProviderSettings: (app?: AppType) => Promise<any>;
       testApiEndpoints: (
         urls: string[],
         options?: { timeoutSecs?: number },