v5.3.8 - mermaid-cli and ComfyUI Desktop Support

Added mermaid-cli, a cross-platform CLI for generating Mermaid diagrams such as flowcharts and sequence diagrams, to bootstrap on all platforms. The @mermaid-js/mermaid-cli npm global package installs in Phase 4 (Linters and Formatters) of both bootstrap.ps1 and bootstrap.sh and provides the mmdc command, and both installs respect -DryRun.

Added ComfyUI Desktop, a Windows-only GUI application for AI image generation, via winget on Windows 11 with package ID Comfy.ComfyUI-Desktop, installed in Phase 5.5 (Development Tools) of bootstrap.ps1. packages.yaml gained a gui_apps category for platform-specific GUI applications plus a mermaid_cli entry under cli_tools, with the header updated to document the new category. windows.ps1 gained package descriptions for mmdc and ComfyUI, and bootstrap.sh notes that ComfyUI requires manual installation on Linux. ComfyUI needs comfy install run after installation to download models and complete setup, covered by a new GUI Applications Post-Installation subsection in the README alongside the mermaid-cli CLI tools entry and the updated CLI tools count.