AI Code Contribution Report — gpt-5-codex

Summary

Updated meta_builder/drawio_meta_builder.py so override discovery records third-party import statements and injects them into the generated meta module header. This ensures rdflib, HTML parsing, and other external dependencies referenced by overrides remain available after regeneration.
Added a regression test that exercises the real override set and asserts the generated module includes every discovered external import. The existing override loader test was also extended to confirm synthetic overrides without external dependencies report an empty import list.
Recorded the change in CHANGELOG.md for visibility.