docs() update from forgetool to clustertool

[kleinarne]

Description
Getting Started still explained the processes using ForgeTool commands and pointed at the ForgeTool repository, so I fixed that.

⚒️ Fixes # no related issue.

⚙️ Type of change

• 🧭 New page (guide, news, landing page)
• 📝 Content update (wording, formatting, SEO)
• 🪛 Bugfix (layout, links, rendering)
• 🎨 UI / styling change
• 🔃 Refactor (no visible change)
• ⚠️ Breaking change (URLs, structure, navigation)

🧪 How Has This Been Tested?

• Built site locally
• Checked page renders correctly
• Verified links
• Checked mobile / desktop layout

📃 Notes:

✔️ Checklist:

• ⚖️ My changes follow the style guidelines of this project
• 👀 I have performed a self-review
• ✍️ Content is clear, accurate, and typo-free
• 🔗 Internal links are valid
• 🖼️ Images are optimized and include alt text (if applicable)
• 📄 I updated related documentation if needed
• 🧪 I described how this change was tested
• 🏷️ The PR title follows the convention:
  • feat(page):
  • fix(content):
  • docs(site):
  • chore(site):

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