feat(providers): add qoder-cn support for Qoder CN (qoder.com.cn)

src/app/api/oauth/[provider]/[action]/route.js

@@ -263,6 +263,7 @@ export async function GET(request, { params }) {
         "codebuddy-cn",
         "codebuddy-intl",
         "qoder",
+        "qoder-cn",
         "grok-cli",
       ];
       let deviceData;
@@ -505,7 +506,7 @@ export async function POST(request, { params }) {
       } else if (provider === "kiro") {
         // Kiro needs extraData (clientId, clientSecret) from device code response
         result = await pollForToken(provider, deviceCode, null, extraData);
-      } else if (provider === "qoder") {
+      } else if (provider === "qoder" || provider === "qoder-cn") {
         // Qoder needs both the PKCE verifier (codeVerifier) and the machineId
         // captured at device-code time (extraData._qoderMachineId) so
         // mapTokens can persist it for COSY signing.