More clear message for character import failure

public/script.js

@@ -6838,6 +6838,11 @@ function importCharacter(file) {
         contentType: false,
         processData: false,
         success: async function (data) {
+            if (data.error) {
+                toastr.error('The file is likely invalid or corrupted.', 'Could not import character');
+                return;
+            }
+
             if (data.file_name !== undefined) {
                 $('#character_search_bar').val('').trigger('input');
                 $("#rm_info_block").transition({ opacity: 0, duration: 0 });

src/character-card-parser.js

@@ -61,6 +61,11 @@ const parse = async (cardUrl, format) => {
                 return PNGtext.decode(chunk.data);
             });
 
+            if (textChunks.length === 0) {
+                console.error('PNG metadata does not contain any character data.');
+                throw new Error('No PNG metadata.');
+            }
+
             return Buffer.from(textChunks[0].text, 'base64').toString('utf8');
         default:
             break;