feat: importierte E-Mails automatisch in IMAP-Ordner verschieben und nach 90 Tagen löschen

- Neuer ImapFolderService verschiebt E-Mails nach erfolgreichem Import in den
  konfigurierbaren Ordner "importiert" (wird bei Bedarf automatisch erstellt)
- Täglicher Cron um 03:00 Uhr verschiebt E-Mails älter als 90 Tage in den
  Papierkorb und leert ihn anschließend
- createImapClient()-Hilfsmethode im EmailDownloadService ausgelagert
- IMAP_IMPORTED_FOLDER und IMAP_TRASH_FOLDER in docker-compose ergänzt

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

paperless-backend/src/email/email-import.service.ts

@@ -12,6 +12,7 @@ import { Task } from '../database/entities/task.entity';
 import { PaperlessService } from '../paperless/paperless.service';
 import * as QRCode from 'qrcode';
 import { EmailPageCacheService } from './email-page-cache.service';
+import { ImapFolderService } from './imap-folder.service';
 import { PdfService } from '../preprocessing/pdf.service';
 import * as path from 'path';
 import * as os from 'os';
@@ -52,6 +53,7 @@ export class EmailImportService {
     private readonly paperlessService: PaperlessService,
     private readonly pdfService: PdfService,
     private readonly pageCache: EmailPageCacheService,
+    private readonly imapFolderService: ImapFolderService,
   ) {}
 
   async ensurePreviews(emailId: number): Promise<void> {
@@ -646,6 +648,12 @@ export class EmailImportService {
           this.logger.log(
             `Email ${firstAtt.EmailMessageId} als verarbeitet markiert.`,
           );
+          const emailEntity = await this.emailRepo.findOne({ where: { Id: firstAtt.EmailMessageId } });
+          if (emailEntity) {
+            this.imapFolderService.moveToImportiert(emailEntity.MessageId).catch(err =>
+              this.logger.error('IMAP-Verschieben fehlgeschlagen: ' + err.message),
+            );
+          }
         }
       }
 

paperless-backend/src/email/email.module.ts

@@ -9,6 +9,7 @@ import { EmailPageCacheService } from './email-page-cache.service';
 
 import { EmailImportController } from './email-import.controller';
 import { EmailImportService } from './email-import.service';
+import { ImapFolderService } from './imap-folder.service';
 import { CorrespondentEmailMapping } from '../database/entities/correspondent-email-mapping.entity';
 import { Task } from '../database/entities/task.entity';
 import { PreprocessingModule } from '../preprocessing/preprocessing.module';
@@ -26,7 +27,7 @@ import { PreprocessingModule } from '../preprocessing/preprocessing.module';
     PreprocessingModule,
   ],
   controllers: [EmailController, EmailImportController],
-  providers: [EmailImportService, EmailPageCacheService],
+  providers: [EmailImportService, EmailPageCacheService, ImapFolderService],
   exports: [EmailPageCacheService],
 })
 export class EmailModule {}

paperless-backend/src/email/imap-folder.service.ts

@@ -0,0 +1,52 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { ImapFlow } from 'imapflow';
+
+@Injectable()
+export class ImapFolderService {
+  private readonly logger = new Logger(ImapFolderService.name);
+
+  constructor(private readonly configService: ConfigService) {}
+
+  private createClient(): ImapFlow {
+    return new ImapFlow({
+      host: this.configService.get<string>('IMAP_HOST', ''),
+      port: this.configService.get<number>('IMAP_PORT', 993),
+      secure: this.configService.get<string>('IMAP_USE_SSL', 'true') === 'true',
+      auth: {
+        user: this.configService.get<string>('IMAP_USERNAME', ''),
+        pass: this.configService.get<string>('IMAP_PASSWORD', ''),
+      },
+      logger: false,
+    });
+  }
+
+  async moveToImportiert(messageId: string): Promise<void> {
+    if (!this.configService.get<string>('IMAP_HOST')) return;
+
+    const importedFolder = this.configService.get<string>('IMAP_IMPORTED_FOLDER', 'importiert');
+    const client = this.createClient();
+    try {
+      await client.connect();
+
+      const mailboxes = await client.list();
+      if (!mailboxes.some(m => m.path === importedFolder)) {
+        await client.mailboxCreate(importedFolder);
+        this.logger.log(`IMAP-Ordner "${importedFolder}" erstellt.`);
+      }
+
+      await client.mailboxOpen('INBOX');
+      const uids = await client.search({ header: { 'message-id': messageId } }, { uid: true });
+      if (Array.isArray(uids) && uids.length > 0) {
+        await client.messageMove(uids, importedFolder, { uid: true });
+        this.logger.log(`E-Mail ${messageId} → "${importedFolder}" verschoben.`);
+      } else {
+        this.logger.warn(`E-Mail ${messageId} nicht in INBOX gefunden (bereits verschoben?).`);
+      }
+    } catch (err: any) {
+      this.logger.error(`IMAP moveToImportiert fehlgeschlagen: ${err.message}`);
+    } finally {
+      await client.logout().catch(() => {});
+    }
+  }
+}