docs: perform automated codebase audit

[samir-alsayad]

This PR contains phase4_report.md, which is the result of a complete codebase audit.

The audit followed a strict 4-phase protocol:

1. Discovery: Mapped files and directories.
2. Directory Pass: Inferred directory responsibilities.
3. File Inspection: Iterated through files to extract line counts, primary responsibilities (via docstrings/headers), and exports.
4. Synthesis: Generated the final report, fixing parsing bugs to accurately reflect file paths and flagging empty files in the anomaly report.

The automation scripts used to generate the report were deleted from the tree to maintain a clean history.

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PR created automatically by Jules for task 7089075121429148331 started by @samir-alsayad

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