feat: add functionality to toggle inbox document source between personal and public scopes

paperless-backend/src/inbox/inbox.service.ts

@@ -1,4 +1,5 @@
 import {
+  BadRequestException,
   ConflictException,
   Injectable,
   Logger,
@@ -190,4 +191,25 @@ export class InboxService {
     }
     return filePath;
   }
+
+  async updateSource(
+    id: string,
+    source: InboxSource,
+    preferredUsername: string | null,
+  ): Promise<void> {
+    const { doc } = await this.resolveDocument(id, preferredUsername);
+
+    if (source === 'all') {
+      doc.Source = 'all';
+      doc.OwnerUsername = null;
+    } else {
+      if (!preferredUsername) {
+        throw new BadRequestException('Benutzername erforderlich für persönlichen Scan');
+      }
+      doc.Source = 'user';
+      doc.OwnerUsername = preferredUsername;
+    }
+
+    await this.documentRepo.save(doc);
+  }
 }