…ent NPE

The previous fix replaced getItemBatch().getItem().getName() with
bi.getItem().getName(), but bi.getItem() or getName() can also be null
(e.g. legacy data, Vmpp/Vmp items). Remove the item name reference
entirely and use a safe generic message instead.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Two independent bugs allowed a transfer issue to proceed even when actual
DB stock was insufficient:

1. Stale in-memory stock check
   The validation loop compared bi.getPharmaceuticalBillItem().getStock()
   .getStock() against qty, but that Stock object is constructed at
   page-load time by createBillItemFromStockDTO() with the available qty
   captured from the bulk DTO query. Any stock movement that occurs after
   the page loads (retail sale, concurrent issue) is invisible to this
   check. Fix: replace with a live DB lookup via StockFacade.find() for
   every item immediately before saveBill() is called, so the check always
   reflects the true current stock level.

2. Negated qty passed to isStockAvailable()
   In the post-save processing loop, qty is negated at line 831 before
   isStockAvailable() is called at line 856. The internal check
   (qty > fetchedStock.getStock()) evaluates as e.g. -10 > 2 → false,
   causing the guard to always return true regardless of actual stock.
   Fix: pass Math.abs(tmpPh.getQty()) so the comparison uses the
   magnitude of the quantity.

Also made the error messages null-safe (bi.getItem() null guard) and
added a clearer message telling the user to refresh when live stock check
fails, since the cause is stale page state.

Closes #20972

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…data

When a transfer issue is settled, the PharmaceuticalBillItem carries a
minimal ItemBatch built from a DTO — only id, batchNo, and rates are set;
the item relationship is null. Both addToStock(pbi, qty, Staff) and
deductFromStock(pbi, qty, Staff) create a new Staff Stock row when none
exists, and they attempt to populate that row's metadata from the batch:

  ItemBatch ib = pharmaceuticalBillItem.getItemBatch();
  Item i = ib != null ? ib.getItem() : null;
  if (i != null) { /* set itemName, barcode, longCode, dateOfExpire, retailsaleRate */ }
  else            { s.setItemName("UNKNOWN"); s.setBarcode(""); s.setLongCode(0L); }

Because the DTO batch has no item loaded, i is always null, so every Staff
Stock row created through a transfer issue is stored with:
  - ITEM_NAME = "UNKNOWN"
  - BARCODE   = ""
  - LONGCODE  = 0
  - DATEOFEXPIRE = null
  - RETAILSALE_RATE = 0.0   (skipped in the else branch)

This does not break stock quantity movement — the JPQL lookup key is
(itemBatch, staff) by ID — but it corrupts the metadata fields used by
stock valuation and expiry reports for in-transit staff stock.

Fix: before accessing ib.getItem(), check whether the item relation is
unloaded (null) while the batch has a valid DB id. If so, call
itemBatchFacade.find(ib.getId()) to obtain the full entity. The loaded
entity is used only for metadata population; the FK already stored on
the Stock row is unchanged. The guard (getItem() == null && getId() != null)
ensures no extra query is issued when the full entity is already loaded
(normal receive-side path where ItemBatch is eagerly fetched from DB).

Applied to both:
  - addToStock(PharmaceuticalBillItem, double qty, Staff)
  - deductFromStock(PharmaceuticalBillItem, double qty, Staff)

Closes #20972

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

…ceuticalBillItem

createEmptyBillItem() (used in generateBillComponent when an item has no
available stock) adds a BillItem with pharmaceuticalBillItem left unset.
Both the live stock validation loop and the zero-qty filter in settle()
dereferenced getPharmaceuticalBillItem() unconditionally, NPEing whenever
such an item was present in the transfer issue.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>