feat: add documentation generation and local serve support

[SynnekOG]

Pull Request

Summary

This PR introduces a new documentation workflow powered by Forge, including commands to generate and serve project documentation locally.

Changes

• Added NatSpec header section for improved documentation organization.
• Updated Makefile with:
  • docs → generates documentation into the $(DOCS_DIR) directory using forge doc.
  • docs-serve → serves the generated documentation locally at http://localhost:3000.
• Added console output for better DX when generating/serving docs.

Motivation

• Streamline developer experience by making it easier to:
  • Generate contract documentation from NatSpec comments.
  • Preview documentation locally during development.
• Improves overall clarity and maintainability of the codebase.

Next Steps

• Configure CI pipeline to auto-generate and publish docs.
• Expand NatSpec coverage across all contracts for richer documentation.