fix: resolve deadlock in config handler during plugin initialization (#1304)

* fix: resolve deadlock in config handler during plugin initialization

The config handler and createBuiltinAgents were calling fetchAvailableModels
with client, which triggers client.provider.list() API call to OpenCode server.
This caused a deadlock because:
- Plugin initialization waits for server response
- Server waits for plugin init to complete before handling requests

Now using cache-only mode by passing undefined instead of client.
If cache is unavailable, the fallback chain will use the first model.

Fixes #1301

* test: add regression tests for deadlock prevention in fetchAvailableModels

Add tests to ensure fetchAvailableModels is called with undefined client
during plugin initialization. This prevents regression on issue #1301.

- config-handler.test.ts: verify config handler does not pass client
- utils.test.ts: verify createBuiltinAgents does not pass client

* test: restore spies in utils.test.ts to prevent test pollution

Add mockRestore() calls for all spies created in test cases to ensure proper cleanup between tests and prevent state leakage.

* test: restore fetchAvailableModels spy

---------

Co-authored-by: robin <robin@watcha.com>
Co-authored-by: justsisyphus <justsisyphus@users.noreply.github.com>

src/plugin-handlers/config-handler.ts

@@ -249,9 +249,15 @@ export function createConfigHandler(deps: ConfigHandlerDeps) {
 
         const prometheusRequirement = AGENT_MODEL_REQUIREMENTS["prometheus"];
         const connectedProviders = readConnectedProvidersCache();
-        const availableModels = ctx.client
-          ? await fetchAvailableModels(ctx.client, { connectedProviders: connectedProviders ?? undefined })
-          : new Set<string>();
+        // IMPORTANT: Do NOT pass ctx.client to fetchAvailableModels during plugin initialization.
+        // Calling client API (e.g., client.provider.list()) from config handler causes deadlock:
+        // - Plugin init waits for server response
+        // - Server waits for plugin init to complete before handling requests
+        // Use cache-only mode instead. If cache is unavailable, fallback chain uses first model.
+        // See: https://github.com/code-yeongyu/oh-my-opencode/issues/1301
+        const availableModels = await fetchAvailableModels(undefined, {
+          connectedProviders: connectedProviders ?? undefined,
+        });
 
         const modelResolution = resolveModelWithFallback({
           uiSelectedModel: currentModel,