Add internal provision endpoint for rSpace Registry

Auth-free POST /api/internal/provision creates Space + system User + ADMIN
membership with starting credits when called by the registry.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/api/internal/provision/route.ts

@@ -0,0 +1,51 @@
+import { NextResponse } from "next/server";
+import { prisma } from "@/lib/prisma";
+
+/**
+ * Internal provision endpoint — called by rSpace Registry when activating
+ * this app for a space. No auth required (only reachable from Docker network).
+ *
+ * Creates Space + a system owner SpaceMember with starting credits.
+ */
+export async function POST(request: Request) {
+  const body = await request.json();
+  const space: string = body.space?.trim();
+  if (!space) {
+    return NextResponse.json({ error: "Missing space name" }, { status: 400 });
+  }
+
+  const existing = await prisma.space.findUnique({ where: { slug: space } });
+  if (existing) {
+    return NextResponse.json({ status: "exists", id: existing.id, slug: existing.slug });
+  }
+
+  const systemEmail = `system+${space}@rspace.online`;
+  const systemDid = `did:system:${space}`;
+
+  const user = await prisma.user.upsert({
+    where: { email: systemEmail },
+    update: { did: systemDid },
+    create: { email: systemEmail, name: `${space}-admin`, did: systemDid },
+  });
+
+  const visibility = body.public ? "public" : "public_read";
+
+  const created = await prisma.space.create({
+    data: {
+      name: space.charAt(0).toUpperCase() + space.slice(1),
+      slug: space,
+      description: body.description || `${space} governance space`,
+      visibility,
+      ownerDid: systemDid,
+      members: {
+        create: {
+          userId: user.id,
+          role: "ADMIN",
+          credits: 50,
+        },
+      },
+    },
+  });
+
+  return NextResponse.json({ status: "created", id: created.id, slug: created.slug }, { status: 201 });
+}