feat: support basic user system

internal/repository/user.sql.go

@@ -0,0 +1,32 @@
+// Code generated by sqlc. DO NOT EDIT.
+// versions:
+//   sqlc v1.30.0
+// source: user.sql
+
+package repository
+
+import (
+	"context"
+)
+
+const getUserByUsername = `-- name: GetUserByUsername :one
+SELECT id, username, password, role, display_name, account_status, last_login_at, created_at
+FROM users
+WHERE username = $1
+`
+
+func (q *Queries) GetUserByUsername(ctx context.Context, username string) (User, error) {
+	row := q.db.QueryRow(ctx, getUserByUsername, username)
+	var i User
+	err := row.Scan(
+		&i.ID,
+		&i.Username,
+		&i.Password,
+		&i.Role,
+		&i.DisplayName,
+		&i.AccountStatus,
+		&i.LastLoginAt,
+		&i.CreatedAt,
+	)
+	return i, err
+}