feat: restructure into XFlow monorepo with Nuxt 4, Modular Onion Monolith, Android client, and Desktop CLI

apps/web/server/api/users/[id]/follow.post.ts

@@ -0,0 +1,40 @@
+import { requireAuth } from '~/server/utils/auth'
+import { prisma } from '~/server/utils/prisma'
+
+export default defineEventHandler(async (event) => {
+  const currentUser = requireAuth(event)
+  const targetIdOrUsername = getRouterParam(event, 'id')
+
+  const targetUser = await prisma.user.findFirst({
+    where: {
+      OR: [
+        { id: targetIdOrUsername },
+        { username: targetIdOrUsername }
+      ]
+    }
+  })
+
+  if (!targetUser) {
+    throw createError({ statusCode: 404, message: 'User not found' })
+  }
+
+  if (targetUser.id === currentUser.id) {
+    throw createError({ statusCode: 400, message: 'You cannot follow yourself' })
+  }
+
+  await prisma.follows.upsert({
+    where: {
+      followerId_followingId: {
+        followerId: currentUser.id,
+        followingId: targetUser.id
+      }
+    },
+    update: {},
+    create: {
+      followerId: currentUser.id,
+      followingId: targetUser.id
+    }
+  })
+
+  return { success: true }
+})