As an editor I want to see constraints violations on Form statements in order to see mistakes in the data and fix them.
**Problem:**
Right now statements on the Form (and Sense) level are not checked for constraints violations.
**Example:**
https://www.wikidata.org/wiki/Lexeme:L123 has two "compound of" statements at the moment. The one on the Lexeme level shows a constraint violation because of a missing mandatory qualifier. The one on the Form level doesn't.
**Screenshots/mockups:**
{F24641669}
**BDD**
GIVEN a statement on a Form
AND that statement violates a constraint
WHEN loading the Lexeme page
THEN the violation should be checked and indicated via the little constraint violation icon
**Acceptance criteria:**
* statements on Forms are checked for constraint violations and indicate them to the user in the same way as constraint violations on Item or Lexeme-level statements
**Open questions:**
* Should `action=wbcheckconstraints&id=L1` automatically check constraints on `L1`’s forms and senses, or should the gadget add the IDs of all the forms and senses to the API request?