feat: add authentication and user management features

- Implemented AuthButton component for Discord sign-in and sign-out functionality.
- Created CopyButton component for copying server IP addresses.
- Developed EventCard and GradeCard components for displaying events and grades.
- Added Footer and Navbar components for site navigation and information.
- Introduced PurchaseButton for handling grade purchases with Stripe integration.
- Created SectionHeader component for consistent section titles.
- Implemented session management with SessionProvider for NextAuth.
- Set up PostgreSQL database with Docker and Prisma for data management.
- Added admin guard functionality to restrict access to certain routes.
- Configured NextAuth with Discord provider for user authentication.
- Defined Prisma schema for user, admin, grade, event, and purchase models.
- Seeded database with initial grades and events data.
- Added SVG hero image for the landing page.
- Extended NextAuth types to include additional user properties.

prisma/schema.prisma

@@ -0,0 +1,112 @@
+generator client {
+  provider = "prisma-client-js"
+}
+
+datasource db {
+  provider = "postgresql"
+  url      = env("DATABASE_URL")
+}
+
+model User {
+  id              String    @id @default(cuid())
+  name            String?
+  email           String?   @unique
+  emailVerified   DateTime?
+  image           String?
+  discordId       String?   @unique
+  discordUsername String?
+  discordAvatar   String?
+  createdAt       DateTime  @default(now())
+  updatedAt       DateTime  @updatedAt
+
+  accounts  Account[]
+  sessions  Session[]
+  purchases Purchase[]
+  admin     Admin?
+}
+
+model Account {
+  id                String   @id @default(cuid())
+  userId            String
+  type              String
+  provider          String
+  providerAccountId String
+  refresh_token     String?  @db.Text
+  access_token      String?  @db.Text
+  expires_at        Int?
+  token_type        String?
+  scope             String?
+  id_token          String?  @db.Text
+  session_state     String?
+
+  user User @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@unique([provider, providerAccountId])
+}
+
+model Session {
+  id           String   @id @default(cuid())
+  sessionToken String   @unique
+  userId       String
+  expires      DateTime
+
+  user User @relation(fields: [userId], references: [id], onDelete: Cascade)
+}
+
+model VerificationToken {
+  identifier String
+  token      String   @unique
+  expires    DateTime
+
+  @@unique([identifier, token])
+}
+
+model Admin {
+  id        String   @id @default(cuid())
+  userId    String   @unique
+  discordId String   @unique
+  createdAt DateTime @default(now())
+
+  user User @relation(fields: [userId], references: [id], onDelete: Cascade)
+}
+
+model Grade {
+  id          String     @id @default(cuid())
+  name        String
+  price       Int
+  description String
+  createdAt   DateTime   @default(now())
+  updatedAt   DateTime   @updatedAt
+
+  purchases Purchase[]
+}
+
+model Event {
+  id          String   @id @default(cuid())
+  title       String
+  description String
+  eventDate   DateTime
+  createdAt   DateTime @default(now())
+  updatedAt   DateTime @updatedAt
+}
+
+enum PurchaseStatus {
+  PENDING
+  PAID
+  FAILED
+  REFUNDED
+}
+
+model Purchase {
+  id              String         @id @default(cuid())
+  userId          String
+  gradeId         String
+  amount          Int
+  status          PurchaseStatus @default(PENDING)
+  stripeSessionId String?
+  createdAt       DateTime       @default(now())
+  updatedAt       DateTime       @updatedAt
+
+  user  User  @relation(fields: [userId], references: [id], onDelete: Cascade)
+  grade Grade @relation(fields: [gradeId], references: [id], onDelete: Restrict)
+}