Added db migrations

api/dc_bot.API/utils/ConnectionStringHelper.cs

@@ -0,0 +1,15 @@
+namespace utils;
+
+public static class ConnectionStringHelper
+{
+    public static string GetConnectionString()
+    {
+        var host = Environment.GetEnvironmentVariable("DB_HOST") ?? "localhost";
+        var port = Environment.GetEnvironmentVariable("DB_PORT") ?? "5432";
+        var database = Environment.GetEnvironmentVariable("DB_NAME") ?? "dc_bot";
+        var username = Environment.GetEnvironmentVariable("DB_USER") ?? "postgres";
+        var password = Environment.GetEnvironmentVariable("DB_PASSWORD") ?? "password";
+
+        return $"Host={host};Port={port};Database={database};Username={username};Password={password}";
+    }
+}