feat(provider): add CodeBuddy CN provider (copilot.tencent.com)

Add Tencent CodeBuddy CN (codebuddy-cn) OAuth provider with full support:
OAuth login (GET poll with state query param), token refresh, 15-model
catalog, /v2 inference endpoint, forced streaming, OpenAI-style reasoning,
and per-model capabilities. Renamed from codebuddy to codebuddy-cn to allow
a future codebuddy-ai variant.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/lib/oauth/constants/oauth.js

@@ -106,7 +106,7 @@ export const CLINE_CONFIG = { ...PROVIDER_OAUTH["cline"] };
 export const GITLAB_CONFIG = { ...PROVIDER_OAUTH["gitlab"] };
 
 // CodeBuddy (Tencent) OAuth Configuration (Browser OAuth Polling Flow)
-export const CODEBUDDY_CONFIG = { ...PROVIDER_OAUTH["codebuddy"] };
+export const CODEBUDDY_CONFIG = { ...PROVIDER_OAUTH["codebuddy-cn"] };
 
 // OAuth timeout (5 minutes)
 export const OAUTH_TIMEOUT = 300000;
@@ -128,5 +128,5 @@ export const PROVIDERS = {
   KILOCODE: "kilocode",
   CLINE: "cline",
   GITLAB: "gitlab",
-  CODEBUDDY: "codebuddy",
+  CODEBUDDY: "codebuddy-cn",
 };

src/lib/oauth/providers.js

@@ -1180,7 +1180,7 @@ const PROVIDERS = {
   // 1. POST stateUrl → get { state, authUrl }
   // 2. Open authUrl in browser
   // 3. Poll tokenUrl with state until success (code 0) or timeout
-  codebuddy: {
+  "codebuddy-cn": {
     config: CODEBUDDY_CONFIG,
     flowType: "device_code",
     requestDeviceCode: async (config) => {
@@ -1212,23 +1212,25 @@ const PROVIDERS = {
       };
     },
     pollToken: async (config, deviceCode) => {
-      const response = await fetch(config.tokenUrl, {
-        method: "POST",
+      // CodeBuddy polls the token endpoint via GET with the state as a query
+      // param (not POST/body) — matches the official CLI's /v2/plugin/auth/token?state=...
+      const response = await fetch(`${config.tokenUrl}?state=${encodeURIComponent(deviceCode)}`, {
+        method: "GET",
         headers: {
-          "Content-Type": "application/json",
           Accept: "application/json",
           "User-Agent": config.userAgent,
           "X-Requested-With": "XMLHttpRequest",
           "X-Domain": "copilot.tencent.com",
           "X-No-Authorization": "true",
           "X-No-User-Id": "true",
+          "X-No-Enterprise-Id": "true",
+          "X-No-Department-Info": "true",
           "X-Product": "SaaS",
         },
-        body: JSON.stringify({ state: deviceCode }),
       });
       if (!response.ok) return { ok: false, data: { error: "request_failed" } };
       const data = await response.json();
-      // code 11217 = pending, code 0 = success
+      // code 11217 = pending (RetryFetchToken), code 0 = success
       if (data.code === 0 && data.data?.accessToken) {
         return {
           ok: true,
@@ -1236,6 +1238,7 @@ const PROVIDERS = {
             access_token: data.data.accessToken,
             refresh_token: data.data.refreshToken || "",
             token_type: data.data.tokenType || "Bearer",
+            expires_in: data.data.expiresIn,
           },
         };
       }
@@ -1245,7 +1248,7 @@ const PROVIDERS = {
     mapTokens: (tokens) => ({
       accessToken: tokens.access_token,
       refreshToken: tokens.refresh_token,
-      expiresIn: 86400,
+      expiresIn: tokens.expires_in || 86400,
       providerSpecificData: {},
     }),
   },