Initial release of swiftui-empty-app-init.

• Initializes a minimal SwiftUI iOS app using XcodeGen in the current directory.
• Generates a single .xcodeproj with exactly one app target and no additional workspaces, packages, or tests (unless explicitly requested).
• Prompts for project name, minimum iOS deployment target, and optional bundle identifier (defaults provided).
• Ensures required prerequisites (Xcode, XcodeGen) are present before proceeding.
• Produces a clean project structure with minimal source files and configuration, ready for immediate development.