migrate importing transaction dialog to composition API and typescript

src/lib/file.ts

@@ -1,3 +1,5 @@
+import type { ImportFileTypeAndExtensions } from '@/core/file.ts';
+
 import { isString } from './common.ts';
 
 export function getFileExtension(filename: string): string {
@@ -9,6 +11,20 @@ export function getFileExtension(filename: string): string {
     return parts[parts.length - 1];
 }
 
+export function findExtensionByType(items: ImportFileTypeAndExtensions[] | undefined, type: string): string | undefined {
+    if (!items || items.length < 1) {
+        return undefined;
+    }
+
+    for (const item of items) {
+        if (item.type === type) {
+            return item.extensions;
+        }
+    }
+
+    return undefined;
+}
+
 export function isFileExtensionSupported(filename: string, supportedExtensions: string): boolean {
     if (!supportedExtensions) {
         return false;