feat(opencode): Phase 7 - Frontend TypeScript type definitions

- Add "opencode" to AppId type in lib/api/types.ts
- Extend McpApps interface with opencode field in types.ts
- Add OpenCode-specific types: OpenCodeModel, OpenCodeProviderOptions,
  OpenCodeProviderConfig, OpenCodeMcpServerSpec
- Add opencodeConfigDir to Settings interface
- Add importOpenCodeFromLive() to providersApi
- Fix type errors across components:
  - AppSwitcher: add opencode to icon/name mappings
  - McpFormModal: add opencode to enabledApps state
  - PromptFormModal/Panel: add opencode filename mapping
  - EndpointSpeedTest: add opencode timeout config
  - useBaseUrlState: add opencode to appType union
  - ProxyToggle: add opencode label
  - App.tsx: handle opencode fallback for SkillsPage
- Update ProxyTakeoverStatus with opencode field (always false)
- Fix test mocks in tests/msw/state.ts

src/components/proxy/ProxyToggle.tsx

@@ -37,7 +37,9 @@ export function ProxyToggle({ className, activeApp }: ProxyToggleProps) {
       ? "Claude"
       : activeApp === "codex"
         ? "Codex"
-        : "Gemini";
+        : activeApp === "gemini"
+          ? "Gemini"
+          : "OpenCode";
 
   const tooltipText = takeoverEnabled
     ? isRunning