feat: Implement invoice generation and emailing functionality

- Added invoice generation logic using DomPDF.
- Integrated invoice data retrieval from the API.
- Implemented language determination for invoices based on customer data.
- Added options to email invoices to customers and admin.
- Included HTML output option for direct viewing in the browser.
- Ensured proper redirection and error handling throughout the process.

assets/scripts.js

@@ -119,7 +119,10 @@ async function connectDevice() {
         // Log connection failure details
         await logCommunication(`Serial connection failed: ${error.message || 'Unknown error'}`, 'disconnected');
         
-        if (openPort = 1){
+        // Check for specific "No port selected" error and show user-friendly message
+        if (error.message && error.message.includes('No port selected by the user')) {
+            progressBar("100", "No device selected, please try again", "#ff6666");
+        } else if (openPort = 1){
           closePort();
           console.log("Closing port");
           alert("System is still trying to close the serial port. If this message continues to come up please refresh this page.");