feat(providers): add Kimchi API key support (dual OAuth + API key)

Kimchi's transport is OpenAI-compatible (Authorization: Bearer) but the
registry declared it OAuth-only, so the dashboard, /api/providers, and
the connection test all rejected API keys. Enable dual auth
(authModes: ["oauth", "apikey"]) and add a kimchi case to
testApiKeyConnection so the Test Connection button works for both modes.
Regenerate the golden snapshot with the Kimchi entries (+ other
previously-missing providers).

open-sse/providers/registry/kimchi.js

@@ -14,7 +14,7 @@ export default {
     },
   },
   category: "freeTier",
-  authModes: ["oauth"],
+  authModes: ["oauth", "apikey"],
   hasOAuth: true,
   transport: {
     baseUrl: "https://llm.kimchi.dev/openai/v1/chat/completions",