feat(server): /v1/pay 下单代理端点 + 购买台账(JWT 鉴权,user→biz_ref 映射)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013nMthbVEmQquxBRKb9Fj8u

server/internal/pay/testutil_test.go

@@ -0,0 +1,40 @@
+package pay
+
+import (
+	"context"
+	"database/sql"
+	"testing"
+	"time"
+
+	"github.com/wangjia/pangolin/server/internal/config"
+	"github.com/wangjia/pangolin/server/internal/store"
+)
+
+func openMigratedSQLite(t *testing.T) *sql.DB {
+	t.Helper()
+	db, err := store.Open(&config.Config{Driver: "sqlite", DSN: ":memory:"})
+	if err != nil {
+		t.Fatalf("open: %v", err)
+	}
+	t.Cleanup(func() { _ = db.Close() })
+	if err := store.MigrateUp(db, "sqlite"); err != nil {
+		t.Fatalf("migrate: %v", err)
+	}
+	if err := store.ApplyCodesLibMigrations(context.Background(), db, "sqlite"); err != nil {
+		t.Fatalf("lib migrate: %v", err)
+	}
+	return db
+}
+
+// seedUser 造最小 users 行(列以 codes/sqlite_helper_test.go::seedUser 为准,
+// 实现时照抄那份 INSERT——含 uuid/email/pw_hash/dp_uuid 等 NOT NULL 列)。
+func seedUser(t *testing.T, db *sql.DB, id int64, uuid string) {
+	t.Helper()
+	_, err := db.Exec(
+		`INSERT INTO users (id, uuid, email, pw_hash, dp_uuid, status, created_at)
+		 VALUES (?, ?, ?, 'x', ?, 'active', ?)`,
+		id, uuid, uuid+"@t.local", uuid, time.Now().UTC())
+	if err != nil {
+		t.Fatalf("seedUser: %v", err)
+	}
+}