feat: integrate Pi backend and Pi Web

pi-web/app/api/auth/providers/route.ts

@@ -0,0 +1,33 @@
+import { ModelRuntime } from "@earendil-works/pi-coding-agent";
+
+export const dynamic = "force-dynamic";
+
+export async function GET() {
+  const modelRuntime = await ModelRuntime.create();
+  const credentials = await modelRuntime.listCredentials();
+  const loggedInProviders = new Set(
+    credentials.filter((credential) => credential.type === "oauth").map((credential) => credential.providerId),
+  );
+  const providers = modelRuntime.getProviders().filter((provider) => provider.auth.oauth);
+
+  const EXCLUDED = new Set(["anthropic"]);
+  const DISPLAY_NAMES: Record<string, string> = {
+    "openai-codex": "ChatGPT Plus/Pro",
+    "github-copilot": "GitHub Copilot",
+  };
+
+  const result = await Promise.all(
+    providers
+      .filter((p) => !EXCLUDED.has(p.id))
+      .map(async (p) => {
+        return {
+          id: p.id,
+          name: DISPLAY_NAMES[p.id] ?? p.name,
+          usesCallbackServer: false,
+          loggedIn: loggedInProviders.has(p.id),
+        };
+      })
+  );
+
+  return Response.json({ providers: result });
+}