### Problem/Motivation Establishes a live-test infrastructure for validating rectors against real contrib modules. Fixes test module identification by searching contrib and adds mandatory zero-match diagnosis with a causes table and diagnostic output. ### Work items - Commit(s): [7d9d3375fc](https://github.com/palantirnet/drupal-rector/commit/7d9d3375fccb), [b3720a2c99](https://github.com/palantirnet/drupal-rector/commit/b3720a2c9958), [c4f9c39163](https://github.com/palantirnet/drupal-rector/commit/c4f9c391635b) ### Credit - Implemented by: @bbrala --- *Filed retroactively as part of the Drupal 12 rector coverage effort. Closed as fixed; credit to be applied to the contributors listed above.* *AI was used extensively to build this change and to file this issue. See [Dries Buytaert: AI-generated Rector rules for Drupal](https://dri.es/ai-generated-rector-rules-for-drupal) and [Björn Brala: Drupal Rector rules are config, not code. Mostly.](https://www.linkedin.com/pulse/drupal-rector-rules-config-code-mostly-bj%C3%B6rn-brala-vfpwe/).*