feat: Add OpenAI-compatible provider nodes

- Support multiple OpenAI-compatible providers with custom prefix/baseUrl
- Add provider nodes CRUD (create/read/update/delete)
- URL building: baseUrl + /chat/completions or /responses
- Model import from /models endpoint
- API key validation via /models
- Usage type safety across all translators
- OAuth token auto-refresh for expired tokens

src/app/api/providers/route.js

@@ -1,6 +1,7 @@
 import { NextResponse } from "next/server";
-import { getProviderConnections, createProviderConnection, isCloudEnabled } from "@/models";
+import { getProviderConnections, createProviderConnection, getProviderNodeById, isCloudEnabled } from "@/models";
 import { APIKEY_PROVIDERS } from "@/shared/constants/config";
+import { isOpenAICompatibleProvider } from "@/shared/constants/providers";
 import { getConsistentMachineId } from "@/shared/utils/machineId";
 import { syncToCloud } from "@/app/api/sync/cloud/route";
 
@@ -32,7 +33,7 @@ export async function POST(request) {
     const { provider, apiKey, name, priority, globalPriority, defaultModel, testStatus } = body;
 
     // Validation
-    if (!provider || !APIKEY_PROVIDERS[provider]) {
+    if (!provider || (!APIKEY_PROVIDERS[provider] && !isOpenAICompatibleProvider(provider))) {
       return NextResponse.json({ error: "Invalid provider" }, { status: 400 });
     }
     if (!apiKey) {
@@ -42,6 +43,27 @@ export async function POST(request) {
       return NextResponse.json({ error: "Name is required" }, { status: 400 });
     }
 
+    let providerSpecificData = null;
+
+    if (isOpenAICompatibleProvider(provider)) {
+      const node = await getProviderNodeById(provider);
+      if (!node) {
+        return NextResponse.json({ error: "OpenAI Compatible node not found" }, { status: 404 });
+      }
+
+      const existingConnections = await getProviderConnections({ provider });
+      if (existingConnections.length > 0) {
+        return NextResponse.json({ error: "Only one connection is allowed for this OpenAI Compatible node" }, { status: 400 });
+      }
+
+      providerSpecificData = {
+        prefix: node.prefix,
+        apiType: node.apiType,
+        baseUrl: node.baseUrl,
+        nodeName: node.name,
+      };
+    }
+
     const newConnection = await createProviderConnection({
       provider,
       authType: "apikey",
@@ -50,6 +72,7 @@ export async function POST(request) {
       priority: priority || 1,
       globalPriority: globalPriority || null,
       defaultModel: defaultModel || null,
+      providerSpecificData,
       isActive: true,
       testStatus: testStatus || "unknown",
     });