feat: Implement manual print dialog with full label printing functionality

Added complete manual print dialog to Web UI based on fManualPrint.cs:
- Created ManualPrintDialog component with all input fields (SID, Vendor Lot, Qty, MFG Date, Reel ID, Supplier, Part No)
- Added printer selection (Left/Right), print count, delete after print checkbox, and barcode input
- Implemented ExecuteManualPrint backend method with ZPL label generation and printer integration
- Added WebSocketServer handler for EXECUTE_MANUAL_PRINT command with full parameter support
- Integrated dialog into Header component with proper error handling via AlertContext

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Handler/Project/WebUI/MachineBridge.cs

@@ -1158,19 +1158,56 @@ namespace Project.WebUI
             }
         }
 
-        public string OpenManualPrint()
+        public string ExecuteManualPrint(string sid, string venderLot, string qty, string mfg, string rid, string spy, string partNo, string printer, int count)
         {
             try
             {
-                // Manual print dialog cannot be opened from web UI
-                // This would require a complex form with reel data input
-                PUB.log.Add("User Request: Manual Print (Web UI)", false);
-                var response = new { success = false, message = "Manual Print is not available in Web UI. Please use the main program." };
-                return JsonConvert.SerializeObject(response);
+                // Parse quantity
+                if (!int.TryParse(qty, out int vqty))
+                {
+                    var response = new { success = false, message = "Please enter quantity as a number" };
+                    return JsonConvert.SerializeObject(response);
+                }
+
+                // Select printer
+                var selectedPrinter = printer.ToLower() == "left" ? PUB.PrinterL : PUB.PrinterR;
+
+                // Create ZPL
+                string zpl = selectedPrinter.makeZPL_210908(new AR.Class.Reel
+                {
+                    SID = sid,
+                    venderLot = venderLot,
+                    venderName = spy,
+                    qty = vqty,
+                    id = rid,
+                    mfg = mfg,
+                    PartNo = partNo,
+                }, SETTING.Data.DrawOutbox, out string qrdata);
+
+                // Print
+                for (int i = 0; i < count; i++)
+                {
+                    var prn = selectedPrinter.Print(zpl);
+                    if (prn.result == false)
+                    {
+                        PUB.log.AddE(prn.errmessage);
+                        var response = new { success = false, message = $"Cannot proceed further due to printing failure: {prn.errmessage}" };
+                        return JsonConvert.SerializeObject(response);
+                    }
+                    else
+                    {
+                        if (i == 0) // Log only first print
+                            PUB.log.Add($"User print completed: {string.Join("|", new string[] { sid, venderLot, spy, qty, rid, mfg, partNo })}", false);
+                    }
+                    System.Threading.Thread.Sleep(100);
+                }
+
+                var response2 = new { success = true, message = $"Successfully printed {count} label(s)" };
+                return JsonConvert.SerializeObject(response2);
             }
             catch (Exception ex)
             {
-                Console.WriteLine($"[ERROR] Failed to open manual print: {ex.Message}");
+                Console.WriteLine($"[ERROR] Failed to execute manual print: {ex.Message}");
                 var response = new { success = false, message = ex.Message };
                 return JsonConvert.SerializeObject(response);
             }