feat: integrate Pi backend and Pi Web

pi-web/app/api/models-config/route.ts

@@ -0,0 +1,43 @@
+import { NextResponse } from "next/server";
+import { readFileSync, writeFileSync, existsSync, mkdirSync } from "fs";
+import { join, dirname } from "path";
+import { getAgentDir } from "@earendil-works/pi-coding-agent";
+import { invalidateModelsCache } from "@/lib/models-cache";
+
+export const dynamic = "force-dynamic";
+
+function getModelsPath(): string {
+  return join(getAgentDir(), "models.json");
+}
+
+function readModelsJson(): Record<string, unknown> {
+  const path = getModelsPath();
+  if (!existsSync(path)) return { providers: {} };
+  try {
+    return JSON.parse(readFileSync(path, "utf8")) as Record<string, unknown>;
+  } catch {
+    return { providers: {} };
+  }
+}
+
+function writeModelsJson(data: Record<string, unknown>): void {
+  const path = getModelsPath();
+  const dir = dirname(path);
+  if (!existsSync(dir)) mkdirSync(dir, { recursive: true });
+  writeFileSync(path, JSON.stringify(data, null, 2), "utf8");
+}
+
+export async function GET() {
+  return NextResponse.json(readModelsJson());
+}
+
+export async function PUT(req: Request) {
+  try {
+    const body = await req.json() as Record<string, unknown>;
+    writeModelsJson(body);
+    invalidateModelsCache();
+    return NextResponse.json({ success: true });
+  } catch (error) {
+    return NextResponse.json({ error: String(error) }, { status: 500 });
+  }
+}