feat: add LiveKit join flow with waiting room and host admission

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/api/meetings/[meetingUuid]/participants/[participantId]/admit/route.ts

@@ -0,0 +1,54 @@
+import { NextResponse } from "next/server"
+
+import { auth } from "@/auth"
+import { prisma } from "@/lib/prisma"
+import { isHostOrCoHost } from "@/lib/meeting-auth"
+
+export async function POST(
+  _request: Request,
+  { params }: { params: Promise<{ meetingUuid: string; participantId: string }> }
+) {
+  const { meetingUuid, participantId } = await params
+
+  const session = await auth()
+  if (!session?.user?.id) {
+    return NextResponse.json({ error: "No autenticado" }, { status: 401 })
+  }
+
+  const meeting = await prisma.meeting.findUnique({
+    where: { uuid: meetingUuid },
+  })
+
+  if (!meeting) {
+    return NextResponse.json(
+      { error: "Reunión no encontrada" },
+      { status: 404 }
+    )
+  }
+
+  const userId = Number(session.user.id)
+  if (!(await isHostOrCoHost(meeting, userId))) {
+    return NextResponse.json(
+      { error: "No tienes permiso para admitir participantes" },
+      { status: 403 }
+    )
+  }
+
+  const participant = await prisma.meetingParticipant.findUnique({
+    where: { id: Number(participantId) },
+  })
+
+  if (!participant || participant.meetingId !== meeting.id) {
+    return NextResponse.json(
+      { error: "Participante no encontrado" },
+      { status: 404 }
+    )
+  }
+
+  const updated = await prisma.meetingParticipant.update({
+    where: { id: participant.id },
+    data: { status: "admitted", admittedAt: new Date() },
+  })
+
+  return NextResponse.json({ id: updated.id, status: updated.status })
+}