feat: Implement pricing page, AI generation/transformation APIs, user/project management, and database schema.

prisma/schema.prisma

@@ -7,16 +7,38 @@ generator client {
 }
 
 // =====================
-// AUTH
+// AUTH & SUBSCRIPTIONS
 // =====================
+model Plan {
+  id           String   @id // e.g., 'free', 'pro', 'master'
+  name         String   @unique
+  displayName  String
+  price        Float
+  description  String
+  maxProjects  Int      // -1 for unlimited
+  maxAiActions Int      // -1 for unlimited
+  features     String[]
+  isPopular    Boolean  @default(false)
+  createdAt    DateTime @default(now())
+  updatedAt    DateTime @updatedAt
+
+  users        User[]
+}
+
 model User {
   id             String   @id @default(cuid())
   name           String?
   email          String   @unique
   hashedPassword String
-  avatar         String?
   bio            String?
-  plan           String   @default("free") // free | pro | master
+  
+  // Legacy string plan (temporarily kept to avoid DB drop errors)
+  plan           String   @default("free")
+
+  // New Subscription
+  planId         String?  @default("free")
+  subscriptionPlan Plan?  @relation(fields: [planId], references: [id])
+  
   aiActionsUsed  Int      @default(0)
   dailyWordGoal  Int      @default(500)
   writingStreak  Int      @default(0)