fix: Handle additional drop and monaco errors

https://harperdb.atlassian.net/browse/STUDIO-616

Author: dawsontoth

src/features/instance/applications/components/ApplicationsSidebar/DropTarget.tsx

@@ -114,9 +114,15 @@ ${humanFileSize(uploadedBytes)} of ${humanFileSize(totalBytes)}`,
 
 				const filePath = getFilePath(targetPath, file);
 				const dataURLResponse = await readAsDataURL(file);
-				const dataURLResult = dataURLResponse.target!.result as string;
+				const dataURLResult = dataURLResponse.target?.result as string | undefined;
+				if (!dataURLResult) {
+					throw new Error(`Failed to read file: ${file.name}`);
+				}
 				const demarcation = 'base64,';
 				const encodingIndex = dataURLResult.indexOf(demarcation);
+				if (encodingIndex === -1) {
+					throw new Error(`Invalid data URL format for file: ${file.name}`);
+				}
 				if (!canceled) {
 					await setComponentFile({
 						...instanceParams,

src/lib/monaco/setup.ts

@@ -49,7 +49,7 @@ import jsonWorker from 'monaco-editor/esm/vs/language/json/json.worker?worker';
 import tsWorker from 'monaco-editor/esm/vs/language/typescript/ts.worker?worker';
 import yamlWorker from 'monaco-yaml/yaml.worker?worker';
 
-const globalScope = self as unknown as { MonacoEnvironment?: monaco.Environment };
+const globalScope = globalThis as unknown as { MonacoEnvironment?: monaco.Environment };
 
 globalScope.MonacoEnvironment = {
 	getWorker(_workerId: string, label: string): Worker {