feat(providers): add Minimax Coding (China) provider

- Add minimax-cn provider with China endpoint (api.minimaxi.com)
- Add provider icon and configuration
- Add validation and test support
- Add API configuration in open-sse

Co-authored-by: Blade096 <46746496+Blade096@users.noreply.github.com>
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/api/providers/[id]/test/route.js

@@ -406,9 +406,14 @@ async function testApiKeyConnection(connection) {
         return { valid, error: valid ? null : "Invalid API key" };
       }
 
-      case "minimax": {
+      case "minimax":
+      case "minimax-cn": {
         // MiniMax uses Claude-compatible API
-        const res = await fetch("https://api.minimax.io/anthropic/v1/messages", {
+        const minimaxEndpoints = {
+          minimax: "https://api.minimax.io/anthropic/v1/messages",
+          "minimax-cn": "https://api.minimaxi.com/anthropic/v1/messages",
+        };
+        const res = await fetch(minimaxEndpoints[connection.provider], {
           method: "POST",
           headers: {
             "x-api-key": connection.apiKey,

src/app/api/providers/validate/route.js

@@ -100,11 +100,13 @@ export async function POST(request) {
 
         case "glm":
         case "kimi":
-        case "minimax": {
+        case "minimax":
+        case "minimax-cn": {
           const claudeBaseUrls = {
             glm: "https://api.z.ai/api/anthropic/v1/messages",
             kimi: "https://api.kimi.com/coding/v1/messages",
             minimax: "https://api.minimax.io/anthropic/v1/messages",
+            "minimax-cn": "https://api.minimaxi.com/anthropic/v1/messages",
           };
           const claudeRes = await fetch(claudeBaseUrls[provider], {
             method: "POST",