feat: monitors worker, auth register, scan polish

Add background DNS/SSL monitor checks, registration API, smoother SSE
with stage labels, improved CDN/WAF detection, light-theme UI polish,
and README roadmap updates.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/api/auth/register/route.ts

@@ -0,0 +1,42 @@
+import { NextRequest, NextResponse } from "next/server";
+import { z } from "zod";
+import bcrypt from "bcryptjs";
+import { prisma } from "@/lib/prisma";
+
+const bodySchema = z.object({
+  email: z.string().email().max(255),
+  password: z.string().min(8).max(128),
+  name: z.string().max(120).optional(),
+});
+
+export async function POST(req: NextRequest) {
+  let body: z.infer<typeof bodySchema>;
+  try {
+    body = bodySchema.parse(await req.json());
+  } catch {
+    return NextResponse.json({ error: "Invalid request" }, { status: 400 });
+  }
+
+  const email = body.email.toLowerCase();
+  const existing = await prisma.user.findUnique({ where: { email } });
+  if (existing) {
+    return NextResponse.json({ error: "Email already registered" }, { status: 409 });
+  }
+
+  const seedEmail = process.env.SEED_ADMIN_EMAIL?.toLowerCase();
+  const role =
+    seedEmail && email === seedEmail ? ("ADMIN" as const) : ("USER" as const);
+
+  const passwordHash = await bcrypt.hash(body.password, 12);
+  const user = await prisma.user.create({
+    data: {
+      email,
+      name: body.name,
+      passwordHash,
+      role,
+    },
+    select: { id: true, email: true, role: true },
+  });
+
+  return NextResponse.json({ user }, { status: 201 });
+}