Add Atuin Server installation and configuration scripts

[j4v3l]

✍️ Description

• Introduced atuin.sh for setting up the Atuin server with automatic updates.
• Added atuin.json for frontend integration, detailing server configuration and usage instructions.
• Created atuin-install.sh to handle installation, PostgreSQL setup, and service management for Atuin server.
• Included detailed server information and client connection instructions in the setup process.

✅ Prerequisites

• 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

• 🐞 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.

[tremor021]

Make a PR on the dev repo