Enable ESLint no-unused-vars rule (#4367)

# Description of Changes
Enable ESLint [no-unused-vars
rule](https://typescript-eslint.io/rules/no-unused-vars/)

frontend/src/utils/automationExecutor.ts

@@ -1,6 +1,5 @@
 import axios from 'axios';
 import { ToolRegistry } from '../data/toolsTaxonomy';
-import { AutomationConfig, AutomationExecutionCallbacks } from '../types/automation';
 import { AUTOMATION_CONSTANTS } from '../constants/automation';
 import { AutomationFileProcessor } from './automationFileProcessor';
 import { ResourceManager } from './resourceManager';

frontend/src/utils/automationFileProcessor.ts

@@ -2,7 +2,7 @@
  * File processing utilities specifically for automation workflows
  */
 
-import axios, { AxiosResponse } from 'axios';
+import axios from 'axios';
 import { zipFileService } from '../services/zipFileService';
 import { ResourceManager } from './resourceManager';
 import { AUTOMATION_CONSTANTS } from '../constants/automation';

frontend/src/utils/fileResponseUtils.ts

@@ -11,11 +11,11 @@ export const getFilenameFromHeaders = (contentDisposition: string = ''): string
   const match = contentDisposition.match(/filename[^;=\n]*=((['"]).*?\2|[^;\n]*)/);
   if (match && match[1]) {
     const filename = match[1].replace(/['"]/g, '');
-    
+
     // Decode URL-encoded characters (e.g., %20 -> space)
     try {
       return decodeURIComponent(filename);
-    } catch (error) {
+    } catch {
       // If decoding fails, return the original filename
       return filename;
     }
@@ -37,9 +37,9 @@ export const createFileFromApiResponse = (
 ): File => {
   const contentType = headers?.['content-type'] || 'application/octet-stream';
   const contentDisposition = headers?.['content-disposition'] || '';
-  
+
   const filename = getFilenameFromHeaders(contentDisposition) || fallbackFilename;
   const blob = new Blob([responseData], { type: contentType });
-  
+
   return new File([blob], filename, { type: contentType });
-};
+};

frontend/src/utils/thumbnailUtils.ts

@@ -346,12 +346,12 @@ export async function generateThumbnailForFile(file: File): Promise<string> {
   // Handle PDF files
   if (file.type.startsWith('application/pdf')) {
     const scale = calculateScaleFromFileSize(file.size);
-    
+
     // Only read first 2MB for thumbnail generation to save memory
     const chunkSize = 2 * 1024 * 1024; // 2MB
     const chunk = file.slice(0, Math.min(chunkSize, file.size));
     const arrayBuffer = await chunk.arrayBuffer();
-    
+
     try {
       return await generatePDFThumbnail(arrayBuffer, file, scale);
     } catch (error) {
@@ -361,7 +361,7 @@ export async function generateThumbnailForFile(file: File): Promise<string> {
           // Try with full file instead of chunk
           const fullArrayBuffer = await file.arrayBuffer();
           return await generatePDFThumbnail(fullArrayBuffer, file, scale);
-        } catch (fullFileError) {
+        } catch {
           console.warn(`Full file PDF processing also failed for ${file.name} - using placeholder`);
           return generatePlaceholderThumbnail(file);
         }
@@ -392,11 +392,11 @@ export async function generateThumbnailWithMetadata(file: File): Promise<Thumbna
   }
 
   const scale = calculateScaleFromFileSize(file.size);
-  
+
   try {
     const arrayBuffer = await file.arrayBuffer();
     const pdf = await pdfWorkerManager.createDocument(arrayBuffer);
-    
+
     const pageCount = pdf.numPages;
     const page = await pdf.getPage(1);
     const viewport = page.getViewport({ scale });
@@ -412,7 +412,7 @@ export async function generateThumbnailWithMetadata(file: File): Promise<Thumbna
 
     await page.render({ canvasContext: context, viewport }).promise;
     const thumbnail = canvas.toDataURL();
-    
+
     pdfWorkerManager.destroyDocument(pdf);
     return { thumbnail, pageCount };
 
@@ -422,8 +422,8 @@ export async function generateThumbnailWithMetadata(file: File): Promise<Thumbna
       const thumbnail = generateEncryptedPDFThumbnail(file);
       return { thumbnail, pageCount: 1 };
     }
-    
+
     const thumbnail = generatePlaceholderThumbnail(file);
     return { thumbnail, pageCount: 1 };
   }
-}
+}