Switch to use ESLint 10 (#5794)

frontend/src/core/hooks/tools/convert/useConvertParameters.ts

@@ -133,7 +133,7 @@ const validateParameters = (params: ConvertParameters): boolean => {
   if (!fromExtension || !toExtension) return false;
 
   // Handle dynamic format identifiers (file-<extension>)
-  let supportedToExtensions: string[] = [];
+  let supportedToExtensions: string[];
   if (fromExtension.startsWith('file-')) {
     // Dynamic format - use 'any' conversion options
     supportedToExtensions = CONVERSION_MATRIX['any'] || [];

frontend/src/core/hooks/tools/removeAnnotations/useRemoveAnnotationsOperation.ts

@@ -71,7 +71,10 @@ const removeAnnotationsProcessor = async (_parameters: RemoveAnnotationsParamete
       processedFiles.push(processedFile);
     } catch (error) {
       console.error('Error processing file:', file.name, error);
-      throw new Error(`Failed to process ${file.name}: ${error instanceof Error ? error.message : 'Unknown error'}`);
+      throw new Error(
+        `Failed to process ${file.name}: ${error instanceof Error ? error.message : 'Unknown error'}`,
+        { cause: error }
+      );
     }
   }
 
@@ -96,4 +99,4 @@ export const useRemoveAnnotationsOperation = () => {
     ...removeAnnotationsOperationConfig,
     getErrorMessage: createStandardErrorHandler(t('removeAnnotations.error.failed', 'An error occurred while removing annotations from the PDF.'))
   });
-};
+};

frontend/src/core/hooks/tools/shared/useToolApiCalls.ts

@@ -77,7 +77,7 @@ export const useToolApiCalls = <TParams = void>() => {
 
       } catch (error) {
         if (axios.isCancel(error)) {
-          throw new Error('Operation was cancelled');
+          throw new Error('Operation was cancelled', { cause: error });
         }
         console.error('[processFiles] Failed', { name: file.name, error });
         failedFiles.push(file.name);

frontend/src/core/hooks/tools/validateSignature/signatureReportPdf.ts

@@ -71,7 +71,7 @@ export const createReportPdf = async (
     cursorY -= 16;
 
     if (entry.error) {
-      cursorY = drawCenteredMessage({
+      drawCenteredMessage({
         page,
         font,
         fontBold,
@@ -86,7 +86,7 @@ export const createReportPdf = async (
     }
 
     if (entry.signatures.length === 0) {
-      cursorY = drawCenteredMessage({
+      drawCenteredMessage({
         page,
         font,
         fontBold,

frontend/src/core/hooks/useCookieConsent.ts

@@ -71,8 +71,7 @@ export const useCookieConsent = ({
           const hasDarkClass = document.documentElement.classList.contains('dark');
           const systemPrefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
 
-          let isDarkMode = false;
-
+          let isDarkMode: boolean;
           if (mantineScheme) {
             isDarkMode = mantineScheme === 'dark';
           } else if (hasLightClass) {
@@ -94,9 +93,8 @@ export const useCookieConsent = ({
           return;
         }
 
-        let themeObserver: MutationObserver | null = null;
         if (!forceLightMode) {
-          themeObserver = new MutationObserver((mutations) => {
+          const themeObserver = new MutationObserver((mutations) => {
             mutations.forEach((mutation) => {
               if (mutation.type === 'attributes' &&
                   (mutation.attributeName === 'data-mantine-color-scheme' ||
@@ -241,7 +239,7 @@ export const useCookieConsent = ({
       const hasDarkClass = document.documentElement.classList.contains('dark');
       const systemPrefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
 
-      let isDarkMode = false;
+      let isDarkMode: boolean;
       if (mantineScheme) {
         isDarkMode = mantineScheme === 'dark';
       } else if (hasLightClass) {