Initial fullstack project setup with Next.js 15, Gin, PostgreSQL and Docker Compose

- Frontend: Next.js 15 (App Router), Auth.js v5, shadcn/ui, MagicUI
- Backend: Go + Gin + GORM with layered architecture
- Auth: Local credentials login with optional Keycloak OAuth binding
- Admin: RBAC user management for admin role
- Dev: Docker Compose with hot reload for both frontend and backend
- Docker: 3-service orchestration (frontend, backend, postgres)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/cmd/api/main.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"log"
+
+	"evanpage-backend/internal/config"
+	"evanpage-backend/internal/db"
+	"evanpage-backend/internal/router"
+)
+
+func main() {
+	cfg := config.Load()
+	db.Init(cfg)
+
+	r := router.Setup(cfg)
+
+	addr := ":" + cfg.ServerPort
+	log.Printf("server starting on %s", addr)
+	if err := r.Run(addr); err != nil {
+		log.Fatalf("server failed: %v", err)
+	}
+}