feat: improve local development and release safety

[shushushv]

Summary

• preflight template web/server ports before dependency installation and support explicit or automatic port overrides
• commit and verify one release version across npm package and official Skill metadata
• preserve quoted Windows task commands and arguments through the native cmd.exe command line
• make development task integration fixtures portable across Windows and Unix systems
• strengthen artifact and publication verification and refresh public documentation

Source audit

• internal public-source checkpoint: 12601f7e9191df721a5674870651aeaeca549436
• GitHub base: 03430491bf5cba93db8ca3bcc536e3d8db8cfe54
• public tree: 0113c047517f4d44bc8d3339c38489c117f95d3c
• public files: 187

Validation

• public-surface and sensitive-information checks passed
• exported GitHub candidate passed GOTOOLCHAIN=go1.25.12 make ci
• clean native Windows clone passed go test -count=1 ./... with Go 1.25.12
• all 25 Windows packages passed with exit code 0