To support the display of constraint violation information in MEX (T400676) we need to fetch the details of current constraint violations from the backend and store them in the wbui pinia store.
The existing implementation of WikibaseQualityConstraints for the front-end is as a bundle of Javascript that is loaded if the `wbEntityId` and `wbIsEditView` flags are set ([source](https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/WikibaseQualityConstraints/+/refs/heads/master/modules/gadget-skip.js)) and hooks into the `wikibase.entityPage.entityLoaded` and `wikibase.statement.saved` hooks ([source](https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/WikibaseQualityConstraints/+/refs/heads/master/modules/gadget.js#41)).
An implementation for MEX would likely need to define a new ResourceLoader module that determines if the `wikibase.wbui2025.lib` module is loaded (`mw.loader.getModuleNames().includes("wikibase.wbui2025.lib")` in the `skipFunction` script?), and in that case hook behaviours into `wikibase.entityPage.entityLoaded` and `wikibase.statement.saved` hooks that populate the wbui pinia store with information about constraint violations by hitting the `wbcheckconstraints` API call, possibly using refactored versions of the existing `fullCheck and `snakCheck` functions.
**Acceptance Criteria**
- [] For wikis where WikibaseQualityConstraints is loaded and MEX is enabled and in use, the wbui2025 pinia store is populated with information about constraint violations on entityInit and statement save.