Initial commit: EGBE chatbot template

Stripped from vercel/chatbot (Apache 2.0):
- Dropped @vercel/* packages and AI Gateway
- Removed artifacts feature (code/text/sheet/image side panel)
- Switched AI provider to @ai-sdk/openai-compatible -> EGBE LiteLLM
- Replaced Vercel Blob upload with data URLs
- Dropped Redis resumable streams and rate limiter (in-memory now)
- Added Dockerfile (Next.js standalone) + entrypoint that runs migrations
- Wired DATABASE_URL, EGBE_AI_API_URL/KEY, NEXT_PUBLIC_BASE_URL for app-deploy.sh

app/(chat)/api/files/upload/route.ts

@@ -0,0 +1,64 @@
+import { NextResponse } from "next/server";
+import { z } from "zod";
+
+import { auth } from "@/app/(auth)/auth";
+
+const MAX_FILE_SIZE = 5 * 1024 * 1024;
+const ALLOWED_TYPES = ["image/jpeg", "image/png", "image/webp", "image/gif"];
+
+const FileSchema = z.object({
+  file: z
+    .instanceof(Blob)
+    .refine((file) => file.size <= MAX_FILE_SIZE, {
+      message: "File size should be less than 5MB",
+    })
+    .refine((file) => ALLOWED_TYPES.includes(file.type), {
+      message: "File type should be JPEG, PNG, WebP, or GIF",
+    }),
+});
+
+export async function POST(request: Request) {
+  const session = await auth();
+
+  if (!session) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  if (request.body === null) {
+    return new Response("Request body is empty", { status: 400 });
+  }
+
+  try {
+    const formData = await request.formData();
+    const file = formData.get("file") as Blob;
+
+    if (!file) {
+      return NextResponse.json({ error: "No file uploaded" }, { status: 400 });
+    }
+
+    const validatedFile = FileSchema.safeParse({ file });
+
+    if (!validatedFile.success) {
+      const errorMessage = validatedFile.error.errors
+        .map((error) => error.message)
+        .join(", ");
+      return NextResponse.json({ error: errorMessage }, { status: 400 });
+    }
+
+    const filename = (formData.get("file") as File).name;
+    const safeName = filename.replace(/[^a-zA-Z0-9._-]/g, "_");
+    const buffer = Buffer.from(await file.arrayBuffer());
+    const dataUrl = `data:${file.type};base64,${buffer.toString("base64")}`;
+
+    return NextResponse.json({
+      url: dataUrl,
+      pathname: safeName,
+      contentType: file.type,
+    });
+  } catch (_error) {
+    return NextResponse.json(
+      { error: "Failed to process request" },
+      { status: 500 }
+    );
+  }
+}