fix(providers): remove Qwen provider support

Qwen OAuth flow (portal.qwen.ai) stopped working reliably; drop the
executor, registry entry, OAuth provider/service, token refresh
profile, usage handler, and related test coverage and baselines.

open-sse/services/usage/misc.js

@@ -1,5 +1,5 @@
 /**
- * Misc usage handlers (Qwen, iFlow, Ollama, GLM, Vercel AI Gateway, Qoder)
+ * Misc usage handlers (iFlow, Ollama, GLM, Vercel AI Gateway, Qoder)
  */
 
 import { proxyAwareFetch } from "../../utils/proxyFetch.js";
@@ -15,23 +15,6 @@ const GLM_QUOTA_URLS = {
 // Returns { balance: "95.50", total_used: "4.50" } (USD as decimal strings).
 const VERCEL_AI_GATEWAY_CREDITS_URL = U("vercel-ai-gateway").url;
 
-/**
- * Qwen Usage
- */
-export async function getQwenUsage(accessToken, providerSpecificData) {
-  try {
-    const resourceUrl = providerSpecificData?.resourceUrl;
-    if (!resourceUrl) {
-      return { message: "Qwen connected. No resource URL available." };
-    }
-
-    // Qwen may have usage endpoint at resource URL
-    return { message: "Qwen connected. Usage tracked per request." };
-  } catch (error) {
-    return { message: "Unable to fetch Qwen usage." };
-  }
-}
-
 /**
  * iFlow Usage
  */