Add tools for extracting token inventory, validating wiki references, and documenting plugin purposes - Introduced `extract.php` to read and analyze PHP source files, extracting classes and functions along with their signatures and line numbers. - Created `plugin-notes.json` to document the purpose and flow of various plugins, enhancing clarity and maintainability. - Added `validate_reference.py` to validate local technical Wiki page names, links, and source fingerprints, ensuring consistency and correctness in documentation.