Update Actions with Lychee and GitHub Token

[pderrenger]

This pull request adds an improved Ultralytics Actions workflow to automatically format code and documentation to the new Ultralytics official standards maintained at https://github.com/ultralytics/actions.

Five individual actions are run by default now including a new broken links check for markdown and HTML files. Disable individual actions by setting them to false or removing their line, i.e. delete 'markdown: true' line to disable markdown formatting.

To customize an action use a pyproject.toml file in this repo. For details see https://github.com/ultralytics/actions.

# Ultralytics 🚀 - AGPL-3.0 license
# Ultralytics Actions https://github.com/ultralytics/actions
# This workflow automatically formats code and documentation in PRs to official Ultralytics standards

name: Ultralytics Actions

on:
  push:
    branches: [main]
  pull_request_target:
    branches: [main]

jobs:
  format:
    runs-on: ubuntu-latest
    steps:
      - name: Run Ultralytics Formatting
        uses: ultralytics/actions@main
        with:
          token: ${{ secrets.GITHUB_TOKEN }}  # automatically generated
          python: true
          docstrings: true
          markdown: true
          spelling: true
          links: true

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improvements in GitHub Workflow and README Documentation for Ultralytics NTC

📊 Key Changes

• 🔄 Updated the GitHub formatting workflow with a new links check.
• 🔑 Added a GITHUB_TOKEN to the workflow to allow automated actions.
• 🏷️ Included a status badge in the README for Ultralytics Actions.
• 📸 Updated the link to the NTCviewer interface screenshot in the README.

🎯 Purpose & Impact

• 🎨 The new links check ensures all hyperlinks in the repository are valid, improving documentation quality.
• 🛠️ GITHUB_TOKEN facilitates secure automation of code formatting checks.
• 📈 The status badge provides a quick visual indication of the workflow's health, enhancing transparency for users.
• 🌐 The updated screenshot URL ensures users see the correct interface example, aiding in understanding the NTCviewer functionality.

[glenn-jocher]