init: hgmj server initial commit

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

models/v/marqueemod/method.go

@@ -0,0 +1,20 @@
+package marqueemod
+
+import (
+	"time"
+
+	"go.mongodb.org/mongo-driver/bson"
+)
+
+func Set(content string) error {
+	if _, err := coll(nil).DeleteMany(bson.M{}); err != nil {
+		return err
+	}
+	_, err := coll(nil).InsertOne(Marquee{Content: content, CreatedAt: time.Now()})
+	return err
+}
+
+func Get() (Marquee, error) {
+	var m Marquee
+	return m, coll(nil).FindOne(&m, bson.M{})
+}