chore: apply ESLint auto-fix across entire backend

Reformats code style (line breaks, indentation, type annotations)
without changing logic. Also includes minor feature additions bundled
in the same lint run (stats service, user-settings groups, agrarmonitor
polling improvements).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

paperless-backend/src/email/email-page-cache.service.ts

@@ -12,7 +12,10 @@ export class EmailPageCacheService {
   private readonly mailsRoot: string;
 
   constructor(configService: ConfigService) {
-    this.mailsRoot = configService.get<string>('MAILS_DATA_DIR', '/mnt/data/mails');
+    this.mailsRoot = configService.get<string>(
+      'MAILS_DATA_DIR',
+      '/mnt/data/mails',
+    );
   }
 
   attachmentDir(attachmentId: number | string): string {
@@ -20,14 +23,23 @@ export class EmailPageCacheService {
   }
 
   previewPath(attachmentId: number | string, page: number): string {
-    return path.join(this.attachmentDir(attachmentId), `page-${page}.preview.png`);
+    return path.join(
+      this.attachmentDir(attachmentId),
+      `page-${page}.preview.png`,
+    );
   }
 
   thumbnailPath(attachmentId: number | string, page: number): string {
-    return path.join(this.attachmentDir(attachmentId), `page-${page}.thumb.png`);
+    return path.join(
+      this.attachmentDir(attachmentId),
+      `page-${page}.thumb.png`,
+    );
   }
 
-  async generate(attachmentId: number | string, renderedImages: string[]): Promise<void> {
+  async generate(
+    attachmentId: number | string,
+    renderedImages: string[],
+  ): Promise<void> {
     const dir = this.attachmentDir(attachmentId);
     await fs.mkdir(dir, { recursive: true });
 
@@ -39,14 +51,22 @@ export class EmailPageCacheService {
 
       try {
         await fs.copyFile(src, previewDest);
-        await sharp(src).resize({ width: THUMBNAIL_WIDTH }).png().toFile(thumbDest);
+        await sharp(src)
+          .resize({ width: THUMBNAIL_WIDTH })
+          .png()
+          .toFile(thumbDest);
       } catch (err: any) {
-        this.logger.warn(`E-Mail Page Cache fehlgeschlagen (Attachment ${attachmentId} Seite ${page}): ${err.message}`);
+        this.logger.warn(
+          `E-Mail Page Cache fehlgeschlagen (Attachment ${attachmentId} Seite ${page}): ${err.message}`,
+        );
       }
     }
   }
 
-  async hasPreview(attachmentId: number | string, page: number): Promise<boolean> {
+  async hasPreview(
+    attachmentId: number | string,
+    page: number,
+  ): Promise<boolean> {
     try {
       await fs.access(this.previewPath(attachmentId, page));
       return true;