create intial db, models, websocket and architecture.

internal/models/message.go

@@ -0,0 +1,16 @@
+package models
+
+import "time"
+
+type Message struct {
+	ID        int       `json:"id"`
+	RoomID    string    `json:"room_id"`
+	User      string    `json:"user"`
+	Text      string    `json:"text"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+type Room struct {
+	ID   string `json:"id"`
+	Name string `json:"name"`
+}