refactor: replace direct Paperless upload with client-side document download functionality

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

@@ -176,21 +176,18 @@ export class InboxController {
     await this.inboxService.updateSource(id, body.source, preferredUsername);
   }
 
-  @Post(':id/save-to-paperless')
-  @HttpCode(204)
-  async saveToPaperless(
+  @Get(':id/download')
+  async download(
     @Param('id') id: string,
-    @Body() body: {
-      title: string;
-      date?: string;
-      documentTypeId?: number;
-      correspondentId?: number;
-      tagIds?: number[];
-    },
     @Request() req: any,
-  ): Promise<void> {
+    @Res({ passthrough: true }) res: Response,
+  ): Promise<StreamableFile> {
     const preferredUsername: string | null = req.user?.preferredUsername ?? null;
-    await this.inboxService.saveToPaperless(id, preferredUsername, body);
+    const { buffer, filename } = await this.inboxService.getEditedPdfBuffer(id, preferredUsername);
+    const { Readable } = await import('stream');
+    res.setHeader('Content-Type', 'application/pdf');
+    res.setHeader('Content-Disposition', `attachment; filename="${encodeURIComponent(filename)}"`);
+    return new StreamableFile(Readable.from(buffer));
   }
 
   @Post(':id/send-email')