fix(opencode): use OpenAI-compatible SDK for APINebula preset

APINebula is an OpenAI-compatible relay (its base URL ends in /v1, matching
its Codex/OpenClaw/Hermes presets), but the OpenCode preset loaded the
@ai-sdk/openai package, which targets the OpenAI Responses API and fails
against chat-completions-only upstreams. Switch the npm field to
@ai-sdk/openai-compatible so requests use the OpenAI Chat Completions format.

src/config/opencodeProviderPresets.ts

@@ -1250,7 +1250,7 @@ export const opencodeProviderPresets: OpenCodeProviderPreset[] = [
     websiteUrl: "https://apinebula.com",
     apiKeyUrl: "https://apinebula.com/02rw5X",
     settingsConfig: {
-      npm: "@ai-sdk/openai",
+      npm: "@ai-sdk/openai-compatible",
       name: "APINebula",
       options: {
         baseURL: "https://apinebula.com/v1",