feat(gemini): add Gemini provider integration (#202)

* feat(gemini): add Gemini provider integration

- Add gemini_config.rs module for .env file parsing
- Extend AppType enum to support Gemini
- Implement GeminiConfigEditor and GeminiFormFields components
- Add GeminiIcon with standardized 1024x1024 viewBox
- Add Gemini provider presets configuration
- Update i18n translations for Gemini support
- Extend ProviderService and McpService for Gemini

* fix(gemini): resolve TypeScript errors, add i18n support, and fix MCP logic

**Critical Fixes:**
- Fix TS2741 errors in tests/msw/state.ts by adding missing Gemini type definitions
- Fix ProviderCard.extractApiUrl to support GOOGLE_GEMINI_BASE_URL display
- Add missing apps.gemini i18n keys (zh/en) for proper app name display
- Fix MCP service Gemini cross-app duplication logic to prevent self-copy

**Technical Details:**
- tests/msw/state.ts: Add gemini default providers, current ID, and MCP config
- ProviderCard.tsx: Check both ANTHROPIC_BASE_URL and GOOGLE_GEMINI_BASE_URL
- services/mcp.rs: Skip Gemini in sync_other_side logic with unreachable!() guards
- Run pnpm format to auto-fix code style issues

**Verification:**
- ✅ pnpm typecheck passes
- ✅ pnpm format completed

* feat(gemini): enhance authentication and config parsing

- Add strict and lenient .env parsing modes
- Implement PackyCode partner authentication detection
- Support Google OAuth official authentication
- Auto-configure security.auth.selectedType for PackyCode
- Add comprehensive test coverage for all auth types
- Update i18n for OAuth hints and Gemini config

---------

Co-authored-by: Jason <farion1231@gmail.com>

src/components/BrandIcons.tsx

@@ -32,3 +32,18 @@ export function CodexIcon({ size = 16, className = "" }: IconProps) {
     </svg>
   );
 }
+
+export function GeminiIcon({ size = 16, className = "" }: IconProps) {
+  return (
+    <svg
+      width={size}
+      height={size}
+      viewBox="0 0 1024 1024"
+      fill="currentColor"
+      className={className}
+      xmlns="http://www.w3.org/2000/svg"
+    >
+      <path d="M471.04 824.32Q512 918.4 512 1024q0-106.24.93-199.68.96-93.44 110.08-162.56t162.56-108.8Q918.4 512 1024 512q-106.24 0-199.68-39.68a524.8 524.8 0 0 1-162.56-110.08 524.8 524.8 0 0 1-110.08-162.56Q512 106.24 512 0q0 106.24-40.96 199.68-39.68 93.44-108.8 162.56a524.8 524.8 0 0 1-162.56 110.08Q106.24 512 0 512q106.24 0 199.68 40.96 93.44 39.68 162.56 108.8t108.8 162.56" />
+    </svg>
+  );
+}