New plain string field on ligne_comptable, positioned after Client in
both form and view displays. Added as a "Facture" column in both the
main table and the entrée/sortie drill-down modal, right after Type.
Backfilled via figli_compta_ledger_update_8002() by extracting an
invoice number from field_notes (or title, same fallback the front-end
libellé already uses) wherever the pattern is unambiguous: literal F,
optional _/-, 2-8 digits, optional "-digits" continuations for a
compound reference (e.g. "F2549-50-51"), optional 0-3 trailing
uppercase letters (e.g. "F250427A"), with a hard boundary right after --
not immediately followed by more letters/digits/underscore. That last
part is what skips "F58_260506_FIGLI" or "F_2601_FIGLI_EPAU": no way to
tell whether the trailing "_xxx" belongs to the reference or is an
unrelated client/description code glued on, so those are left blank
rather than guessed, per explicit instruction to skip when unsure.
Verified the pattern against every existing ligne_comptable's
notes/title before writing the migration: 319 confident matches with no
false positives found on manual review of the full list, 1236 left
blank. Applied via drush updb, config exported.
