feat: migrate Canvas and Groups API to Prisma ORM

app/server/api/canvas/[id].delete.ts

@@ -1,15 +1,16 @@
 import { requireAuth } from '~/server/utils/auth'
-import { canvases } from '~/server/utils/db'
+import { prisma } from '~/server/utils/prisma'
 
 export default defineEventHandler(async (event) => {
-  requireAuth(event)
+  const user = requireAuth(event)
   const id = getRouterParam(event, 'id')
+  if (!id) throw createError({ statusCode: 400, message: 'Canvas ID is required' })
 
-  if (!canvases.has(id || '')) {
-    throw createError({ statusCode: 404, message: 'Canvas not found' })
-  }
+  const canvas = await prisma.canvas.findUnique({ where: { id } })
+  if (!canvas) throw createError({ statusCode: 404, message: 'Canvas not found' })
+  if (canvas.ownerId !== user.id) throw createError({ statusCode: 403, message: 'Access denied' })
 
-  canvases.delete(id || '')
+  await prisma.canvas.delete({ where: { id } })
 
   return { success: true, message: 'Canvas deleted' }
-})  
+})