chore: accept PDF files in receipt upload dialog (refs #182)

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

frontend/src/features/maintenance/components/AddReceiptDialog.tsx

@@ -47,11 +47,17 @@ export const AddReceiptDialog: React.FC<AddReceiptDialogProps> = ({
           file.name.toLowerCase().endsWith('.heif')
         );
       }
+      if (format === 'application/pdf') {
+        return (
+          file.type === 'application/pdf' ||
+          file.name.toLowerCase().endsWith('.pdf')
+        );
+      }
       return file.type === format;
     });
 
     if (!isValidType) {
-      return 'Invalid file type. Accepted formats: JPEG, PNG, HEIC';
+      return 'Invalid file type. Accepted formats: JPEG, PNG, HEIC, PDF';
     }
 
     if (file.size > DEFAULT_MAX_FILE_SIZE) {
@@ -207,10 +213,10 @@ export const AddReceiptDialog: React.FC<AddReceiptDialogProps> = ({
             textAlign="center"
             fontWeight={500}
           >
-            {isDragging ? 'Drop image here' : 'Drag and drop an image, or tap to browse'}
+            {isDragging ? 'Drop file here' : 'Drag and drop an image or PDF, or tap to browse'}
           </Typography>
           <Typography variant="caption" color="text.secondary" textAlign="center">
-            JPEG, PNG, HEIC -- up to 10MB
+            JPEG, PNG, HEIC, PDF -- up to 10MB
           </Typography>
         </Box>
 
@@ -265,7 +271,7 @@ export const AddReceiptDialog: React.FC<AddReceiptDialogProps> = ({
         accept={DEFAULT_ACCEPTED_FORMATS.join(',')}
         onChange={handleInputChange}
         style={{ display: 'none' }}
-        aria-label="Select receipt image"
+        aria-label="Select receipt file"
       />
     </Dialog>
   );

frontend/src/shared/components/CameraCapture/types.ts

@@ -127,6 +127,7 @@ export const DEFAULT_ACCEPTED_FORMATS = [
   'image/png',
   'image/heic',
   'image/heif',
+  'application/pdf',
 ];
 
 /** Default max file size (10MB) */