chore(BA-2212): Add rover cli installation in install-dev script

[seedspirit]

resolves #5663 (BA-2213)

Checklist: (if applicable)

• Milestone metadata specifying the target backport version
• Mention to the original issue
• Installer updates including:
  • Fixtures for db schema changes
  • New mandatory config options
• Update of end-to-end CLI integration tests in ai.backend.test
• API server-client counterparts (e.g., manager API -> client SDK)
• Test case(s) to:
  • Demonstrate the difference of before/after
  • Demonstrate the flow of abstract/conceptual models with a concrete implementation
• Documentation
  • Contents in the docs directory
  • docstrings in public interfaces and type annotations

[Copilot]

Pull Request Overview

This PR adds Apollo Rover CLI installation to the development setup script to support Supergraph generation capabilities. The change integrates Rover CLI installation into the existing Backend.AI development environment setup process.

• Adds a new install_rover_cli() function that downloads and configures Apollo Rover CLI
• Integrates Rover CLI installation into the configure_backendai() function
• Sets up necessary environment variables and shell configuration for Rover CLI

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[Copilot]

Downloading and executing a script directly from the internet without verification poses a security risk. Consider adding checksum verification or using a pinned version to ensure the integrity of the downloaded script.

Suggested change

	curl -sSL https://rover.apollo.dev/nix/latest | sh
	# Download the Rover install script and verify its checksum before executing
	ROVER_INSTALL_URL="https://rover.apollo.dev/nix/latest"
	ROVER_INSTALL_SCRIPT="/tmp/rover_install.sh"
	EXPECTED_SHA256="REPLACE_WITH_KNOWN_GOOD_SHA256"
	curl -sSL "$ROVER_INSTALL_URL" -o "$ROVER_INSTALL_SCRIPT"
	ACTUAL_SHA256=$(sha256sum "$ROVER_INSTALL_SCRIPT" | awk '{print $1}')
	if [ "$ACTUAL_SHA256" != "$EXPECTED_SHA256" ]; then
	echo -e "${RED}ERROR: Checksum verification failed for Rover install script.${WHITE}"
	echo -e "${YELLOW}Expected: $EXPECTED_SHA256${WHITE}"
	echo -e "${YELLOW}Actual: $ACTUAL_SHA256${WHITE}"
	rm -f "$ROVER_INSTALL_SCRIPT"
	return 1
	fi
	sh "$ROVER_INSTALL_SCRIPT"
	rm -f "$ROVER_INSTALL_SCRIPT"

[Copilot]

The installation process lacks error handling and user feedback. If the Rover CLI installation fails, the script will continue without indication. Consider adding error checking and using the existing show_info function to provide user feedback about the installation progress.