fix(cli): keep openai passthrough during ocx init so gpt-* models still route (issue #261)

[Wibias]

Summary

Fixes the root cause behind #261.

The reporter selected Kimi as their default provider, then every built-in gpt-* request 404'd with No enabled canonical OpenAI provider for model: gpt-5.6-sol.

Root cause

ocx init assembled the saved config by spreading the defaults and then replacing the whole providers map with just the chosen provider:

s const config = { ...getDefaultConfig(), providers: { [providerName]: providerConfig }, // wipes the baseline openai passthrough defaultProvider: providerName, };

The default config ships an openai forward provider that passes Codex's ChatGPT login through to the backend. The router sends every bare gpt-* model straight to providers["openai"] regardless of defaultProvider:

s if (isBareOpenAiFamilyModel(modelId)) { const provider = config.providers[OPENAI_CODEX_PROVIDER_ID]; // "openai" if (provider && provider.disabled !== true) return routeResult(...); throw new NoEnabledOpenAiProviderError(modelId); // 404 }

So the moment ocx init dropped the openai provider, gpt-* routing broke. The default being Kimi was a red herring; the passthrough deletion was the actual bug.

Fix

1. buildInitConfig (extracted, pure, tested) now layers the chosen provider on top of the baseline defaults instead of replacing them, so the openai passthrough survives.
2. ocx init prints a note when a non-openai default is chosen, so users know gpt-* still routes through their ChatGPT login.
3. Clearer prompts: "Choose your default provider (you can add more later):" and "Select default provider (number):".
4. More actionable error message on NoEnabledOpenAiProviderError as a safety net for configs that still end up without an openai provider.

Changes

• src/cli/init.ts: Preserve baseline providers, extract buildInitConfig, add note, clarify prompts
• src/router.ts: Actionable NoEnabledOpenAiProviderError message
• tests/init-config.test.ts: Cover passthrough preservation, openai-as-default, and port

Verification

• bun test on init-config, startup-prompt, router: 26 pass, 0 fail
• bun run typecheck: clean