major: Set MTU for docker globally to 1400

[venkatamutyala]

Configure Docker MTU settings and restart service.

[Copilot]

Pull request overview

Configures Docker’s daemon MTU to 1400 during developer environment setup by writing a Docker daemon config and restarting the Docker service.

Changes:

• Write /etc/docker/daemon.json with {"mtu": 1400} during setup
• Restart Docker after applying the MTU setting

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

This command overwrites /etc/docker/daemon.json unconditionally. If the host already has Docker daemon configuration (e.g., registry-mirrors, insecure-registries, log-driver, etc.), this will clobber it and may break Docker on reruns. Consider preserving existing JSON and only setting/overriding the "mtu" key (e.g., read existing file if present and merge), or gate the write behind a check when the file doesn’t exist.

Suggested change

	sudo mkdir -p /etc/docker && echo '{"mtu": 1400}' | sudo tee /etc/docker/daemon.json > /dev/null && sudo systemctl restart docker
	sudo mkdir -p /etc/docker
	TMP_DOCKER_DAEMON_JSON=$(mktemp)
	if sudo test -s /etc/docker/daemon.json; then
	sudo python3 -c 'import json; import sys; p = sys.argv[1]; data = json.load(open(p)); data["mtu"] = 1400; json.dump(data, sys.stdout)' /etc/docker/daemon.json | sudo tee "$TMP_DOCKER_DAEMON_JSON" > /dev/null
	else
	echo '{"mtu": 1400}' | sudo tee "$TMP_DOCKER_DAEMON_JSON" > /dev/null
	fi
	sudo mv "$TMP_DOCKER_DAEMON_JSON" /etc/docker/daemon.json
	sudo systemctl restart docker