refactor: update devcontainer features and remove MCP adapter tests

Author: Marvin Zhang

.devcontainer/devcontainer.json

@@ -7,7 +7,8 @@
 	// Features to add to the dev container. More info: https://containers.dev/features.
 	"features": {
 		"ghcr.io/devcontainers/features/github-cli:1": {},
-		"ghcr.io/devcontainers/features/docker-in-docker:2": {}
+		"ghcr.io/devcontainers/features/docker-in-docker:2": {},
+		"ghcr.io/devcontainers/features/sshd:1": {}
 	},
 
 	// Use 'forwardPorts' to make a list of ports inside the container available locally.