feat: support basic file presenting

frontend/src/core/utils/files.ts

@@ -0,0 +1,25 @@
+export function getFileName(filepath: string) {
+  return filepath.split("/").pop()!;
+}
+
+export function getFileExtension(filepath: string) {
+  const fileName = getFileName(filepath);
+  const extension = fileName.split(".").pop()!.toLocaleLowerCase();
+  switch (extension) {
+    case "doc":
+    case "docx":
+      return "Word";
+    case "md":
+      return "Markdown";
+    case "txt":
+      return "Text";
+    case "ppt":
+    case "pptx":
+      return "PowerPoint";
+    case "xls":
+    case "xlsx":
+      return "Excel";
+    default:
+      return extension.toUpperCase();
+  }
+}