初始提交：姜十三论坛 Jiang13 Forum

轻量自用论坛，Go 单二进制 + React SPA 内嵌 + SQLite。

Co-authored-by: Cursor <cursoragent@cursor.com>

model/db.go

@@ -0,0 +1,46 @@
+package model
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+var DB *gorm.DB
+
+// InitDB 初始化 SQLite 并自动迁移
+func InitDB(dbPath string) error {
+	dir := filepath.Dir(dbPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("创建数据库目录失败: %w", err)
+	}
+
+	db, err := gorm.Open(sqlite.Open(dbPath), &gorm.Config{
+		Logger: logger.Default.LogMode(logger.Warn),
+	})
+	if err != nil {
+		return fmt.Errorf("连接 SQLite 失败: %w", err)
+	}
+
+	sqlDB, err := db.DB()
+	if err != nil {
+		return err
+	}
+	sqlDB.SetMaxOpenConns(1)
+
+	if err := db.AutoMigrate(
+		&User{}, &Board{}, &Post{}, &Comment{},
+		&PostLike{}, &PostFavorite{},
+	); err != nil {
+		return fmt.Errorf("自动迁移失败: %w", err)
+	}
+
+	DB = db
+	log.Println("[model] SQLite 数据库初始化完成:", dbPath)
+	return nil
+}