Fix time entry 500 and inventory edit pencil visibility

- Remove parseInt() from time entry worker select — GUIDs were destroyed
  to NaN → sent as null → FindByIdAsync(null) threw 500
- Ledger pencil: also show for Adjustment rows (no PO) so scan-without-job
  entries get an edit button, not just JobUsage rows
- InventoryController: always write JobUsage type for scan-based logs;
  accept Adjustment in edit endpoints; promote Adjustment→JobUsage when
  a job is assigned via edit

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

src/PowderCoating.Web/Controllers/InventoryController.cs

@@ -1424,8 +1424,8 @@ public class InventoryController : Controller
             }
 
             var userId = _userManager.GetUserId(User) ?? string.Empty;
-            var txnType = jobId.HasValue ? InventoryTransactionType.JobUsage
-                : (Enum.TryParse<InventoryTransactionType>(transactionType, out var parsed) ? parsed : InventoryTransactionType.Adjustment);
+            // Scan-based logging always records as JobUsage; Adjustment is for manual stock corrections only
+            var txnType = InventoryTransactionType.JobUsage;
 
             item.QuantityOnHand -= quantity;
             item.UpdatedAt = DateTime.UtcNow;
@@ -1719,8 +1719,9 @@ public class InventoryController : Controller
         var txn = await _unitOfWork.InventoryTransactions.GetByIdAsync(id, false,
             t => t.Job, t => t.InventoryItem);
         if (txn == null) return NotFound();
-        if (txn.TransactionType != InventoryTransactionType.JobUsage)
-            return BadRequest("Only JobUsage transactions can be edited here.");
+        if (txn.TransactionType != InventoryTransactionType.JobUsage
+            && txn.TransactionType != InventoryTransactionType.Adjustment)
+            return BadRequest("Only usage transactions can be edited here.");
 
         var allJobs = await _unitOfWork.Jobs.FindAsync(
             j => !j.JobStatus.IsTerminalStatus,
@@ -1762,7 +1763,8 @@ public class InventoryController : Controller
     {
         var txn = await _unitOfWork.InventoryTransactions.GetByIdAsync(id);
         if (txn == null) return NotFound();
-        if (txn.TransactionType != InventoryTransactionType.JobUsage)
+        if (txn.TransactionType != InventoryTransactionType.JobUsage
+            && txn.TransactionType != InventoryTransactionType.Adjustment)
             return BadRequest();
 
         if (jobId.HasValue)
@@ -1777,6 +1779,10 @@ public class InventoryController : Controller
             txn.Reference = null;
         }
 
+        // Promote Adjustment→JobUsage when a job is assigned so it shows in Powder Usage By Job tab
+        if (jobId.HasValue && txn.TransactionType == InventoryTransactionType.Adjustment)
+            txn.TransactionType = InventoryTransactionType.JobUsage;
+
         txn.Notes = notes?.Trim();
         txn.TransactionDate = transactionDate.Kind == DateTimeKind.Utc
             ? transactionDate : DateTime.SpecifyKind(transactionDate, DateTimeKind.Utc);