[CI] Migrate to npm-managed local Hugo and standardise Makefile targets

Current Behavior

Currently, the layer5io/academy-example template relies on a globally installed Hugo binary or inconsistent npx invocations for local development. Because this repository serves as the blueprint for all Layer5 academies, any new academy generated from this template automatically inherits these problematic build scripts, leading to version mismatches and CI discrepancies for new contributors.

Desired Behavior

A contained, highly reproducible local development environment where dependencies are strictly managed via npm. Running make setup should fetch the correct hugo-extended NPM dependency. Subsequent commands (make site, make build, make serve, etc.) should automatically route to this local binary, eliminating the need for a global Hugo installation.

Implementation

This approach standardizes the build process for the template, ensuring all future academy repositories are created with correct CI hygiene from day one. This matches the migrations already applied to meshery/meshery, digitalocean-academy, and exoscale-academy.

Specific changes should include:

• Makefile: Add a check-deps target to validate npm and the local hugo binary before execution. Reroute build, site, serve, and clean to trigger their respective npm run scripts.
• package.json: Add dev:* scripts (e.g., dev:build, dev:clean, dev:site) to explicitly handle Hugo commands with the correct flags, relying on the local node module instead of a global installation.
• Documentation: Update README.md and CONTRIBUTING.md to remove references to installing Hugo globally, emphasizing the unified make setup -> make site workflow for newcomers.

Acceptance Tests

• make setup installs the local hugo-extended dependency cleanly.
• make site successfully spins up the local development server using the NPM-managed binary.
• make clean correctly wipes the build cache using the local binary.
• A user without a globally installed Hugo can build the template site from a fresh clone.

Contributor Guide and Resources

• 📚 Instructions for contributing to academy-example
• Layer5 documentation site and source
• 🎨 Wireframes and designs for Layer5 site in Figma (open invite)
• 🙋🏾🙋🏼 Questions: Layer5 Discussion Forum and Layer5 Community Slack

Contributor Guide and Resources

• 📚 Instructions for contributing to academy-example
  • academy-template documentation site, example and theme
• 🎨 Wireframes and designs for Layer5 site in Figma (open invite)
• 🙋🏾🙋🏼 Questions: Layer5 Discussion Forum and Layer5 Community Slack