fix: cap a manufacture entry at the job card's pending production

Entries from operations without their own BOM carry no For Quantity,
so the finished-good reconciliation cannot run for them and a draft
created before other entries were submitted could still over-produce.

Validate every job-card manufacture entry against the job card
directly: finished goods plus process loss must fit in what the job
card still has left to produce after earlier submitted entries.

erpnext/stock/doctype/stock_entry/stock_entry.py

@@ -319,6 +319,7 @@ class StockEntry(StockController, SubcontractingInwardController):
 		self.validate_batch()
 		self.validate_inspection()
 		self.validate_fg_completed_qty()
+		self.validate_job_card_pending_production()
 		self.validate_difference_account()
 		self.validate_job_card_item()
 		self.set_purpose_for_stock_entry()
@@ -1475,6 +1476,40 @@ class StockEntry(StockController, SubcontractingInwardController):
 				(flt(self.process_loss_qty) / flt(self.fg_completed_qty)) * 100
 			)
 
+	def validate_job_card_pending_production(self):
+		"""A draft created before other entries were submitted must not book more than the job
+		card still has left; without this, a stale draft over-produces the finished good."""
+		if self.purpose != "Manufacture" or not self.job_card:
+			return
+
+		job_card = frappe.get_doc("Job Card", self.job_card)
+		if job_card.is_corrective_job_card or job_card.is_subcontracted:
+			return
+
+		precision = frappe.get_precision("Stock Entry Detail", "qty")
+		pending_qty = flt(
+			flt(job_card.get_qty_to_produce())
+			- flt(job_card.manufactured_qty)
+			- flt(job_card.get_consumed_process_loss()),
+			precision,
+		)
+		finished_qty = flt(sum(flt(d.transfer_qty) for d in self.items if d.is_finished_item), precision)
+		entry_qty = flt(finished_qty + flt(self.process_loss_qty), precision)
+
+		if entry_qty > pending_qty:
+			uom = job_card.stock_uom
+			frappe.throw(
+				_(
+					"The Job Card {0} has only {1} left to produce, but this entry books {2} ({3} finished goods and {4} process loss). Cancel or update its other manufacture entries first."
+				).format(
+					frappe.bold(self.job_card),
+					frappe.bold(f"{pending_qty} {uom}"),
+					frappe.bold(f"{entry_qty} {uom}"),
+					f"{finished_qty} {uom}",
+					f"{flt(self.process_loss_qty, precision)} {uom}",
+				)
+			)
+
 	def get_pending_process_loss_qty(self):
 		"""Loss this entry should still book: the job card's unbooked loss when the entry
 		belongs to one, else the largest operation loss on the work order (legacy flow)."""