Initial project structure for Wrenn Sandbox

Set up directory layout, Makefiles, go.mod files, docker-compose,
and empty placeholder files for all packages.

go.mod

@@ -0,0 +1,17 @@
+module github.com/wrenn-dev/wrenn-sandbox
+
+go 1.23.0
+
+require (
+	github.com/firecracker-microvm/firecracker-go-sdk v1.1.1
+	github.com/go-chi/chi/v5 v5.2.1
+	github.com/gorilla/websocket v1.5.3
+	github.com/jackc/pgx/v5 v5.7.4
+	github.com/mdlayher/vsock v1.2.1
+	github.com/pressly/goose/v3 v3.24.3
+	github.com/prometheus/client_golang v1.21.1
+	github.com/rs/cors v1.11.1
+	golang.org/x/crypto v0.36.0
+	google.golang.org/grpc v1.71.0
+	google.golang.org/protobuf v1.36.5
+)