Refactor: migrate Jupyter Notebook to uv-based installation with update support

[MickLesk]

✍️ Description

This PR refactors the installation and update logic for Jupyter Notebook to use the modern uv-based Python virtual environment under /opt/jupyter.
It ensures consistent, isolated package management and replaces legacy pip3 install jupyter usage.

Additionally, the update_script():

• Migrates legacy containers using system-wide Python to uv venv
• Updates existing .venv installations
• Rewrites the systemd service if it still references the legacy jupyter binary

🔗 Related PR / Issue

Link: #

✅ Prerequisites (X in brackets)

• Self-review completed – Code follows project standards.
• Tested thoroughly – Changes work as expected.
• No security risks – No hardcoded secrets, unnecessary privilege escalations, or permission issues.

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🛠️ Type of Change (X in brackets)

• 🐞 Bug fix – Resolves an issue without breaking functionality.
• ✨ New feature – Adds new, non-breaking functionality.
• 💥 Breaking change – Alters existing functionality in a way that may require updates.
• 🆕 New script – A fully functional and tested script or script set.
• 🌍 Website update – Changes to website-related JSON files or metadata.
• 🔧 Refactoring / Code Cleanup – Improves readability or maintainability without changing functionality.
• 📝 Documentation update – Changes to README, AppName.md, CONTRIBUTING.md, or other docs.