Add Heroshot to Mockups section

[omachala]

Hi! I'd like to add Heroshot to the Mockups section.

Heroshot is a free, open-source CLI tool for automating documentation screenshots:

• Config-based workflows (define once, update forever)
• Theme-aware captures (light/dark mode)
• Visual element picker in the browser
• Framework integrations (VitePress, Docusaurus, React, Vue)

It fits well alongside MockupsJar and MockUPhone as it helps create consistent screenshots for documentation and product pages.

Thank you for maintaining this resource!