* NEW: Improve phpunit test coverage for Commande, Propal and Facture
Add line CRUD (addline/updateline/deleteLine) and total-consistency
assertions, reuse the specimen-invariant regression check (previously
only in FactureTest) across all three, and add a new integration test
covering the full Propal -> Commande -> Facture conversion chain
(thirdparty, notes, totals and object_linked propagation).
Two shared assertions were added to CommonClassTest for this:
assertLineTotalsMatchHeader() and assertMatchesFreshSpecimen().
* Update commande.class.php
* FIX PropalCommandeFactureWorkflowTest reads wrong invoice after createFromOrder
Facture::createFromOrder() returns a status flag (1/-1), not the new
invoice id, unlike Commande::createFromProposal(). The test was doing
fetch($result) with $result==1, which happened to no-op locally (no
invoice with rowid=1) but fetched an unrelated invoice in CI, causing
a spurious thirdparty mismatch. Use $facture->id, already set by
create() inside createFromOrder(), like every other caller of this
method does.
