Improve R package compliance with R CMD check and enhance graph rendering compatibility

[SpatLyu]

This pull request introduces a series of changes aimed at improving package quality, documentation accuracy, and compatibility with rendering libraries:

• Compliance Enhancements:

  • Removed LazyData from DESCRIPTION to eliminate unnecessary NOTE.
  • Declared missing function runif to resolve undefined NOTE.
  • Addressed all remaining R CMD check NOTEs.

• Documentation:

  • Regenerated documentation using roxygen2 version 7.3.2.

• License:

  • Adopted the MIT License to standardize legal usage and distribution.

• Graph Rendering Fix:

  • Replaced unsupported 'dot' layout in DiagrammeR::render_graph() with 'neato' to restore graph rendering functionality.