package:cognitive_complexity v0.2.3+2

• Streamline README.md into a focused, scannable TL;DR.
• Extract deep-dive reference documentation into modular guides under doc/:
  • doc/scoring.md: Scoring matrix, nesting multipliers, and Dart 3 AST rules.
  • doc/cli.md: Command-line options, git diff delta evaluation, and CI ratcheting.
  • doc/data_flow.md: Statement data-flow analysis, method extraction theory, and programmatic API.
  • doc/github_actions.md: Complete GitHub Action workflow setup, parameters, and fork security permissions.