New field_flag: free-tagging taxonomy reference (multi-value,
auto-create) on ligne_comptable, for marking a line with an
unstructured problem description (e.g. "client impayé") that can't be
detected automatically the way the répartition écart already is.
- New "Signalement" column, inline-editable like Client/Facture/Libellé
(comma-separated tags, datalist autocomplete, server-side auto-create
of unknown tags -- same pattern LedgerActionsController already used
for Client, now shared via findOrCreateTerm()).
- New "Signalées uniquement" filter, mirroring "Écarts uniquement".
- Flagged rows get a distinct amber left-edge accent (box-shadow, not
border) so a row that's both in écart and signalée shows both
indicators without one overwriting the other.
- Native node add/edit form gets the field for free via core's
entity_reference_autocomplete_tags widget.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>