feat: add Agrarmonitor integration module

- New backend module (agrarmonitor) with status check and device registration
- Frontend settings tab with connection status display and registration form
- Environment variables for base URLs, credentials, cookie path and encryption key
- Docker Compose env passthrough for agrarmonitor config

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

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

@@ -0,0 +1,86 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import {
+  createAgrarmonitorClient,
+  FileCookieStore,
+  AesGcmCookieEncryptor,
+  type AgrarmonitorConnectorResult,
+} from 'agrarmonitor-connector';
+
+export interface AgrarmonitorStatusDto {
+  connected: boolean;
+  registriert: boolean | null;
+  freigeschaltet: boolean | null;
+  error?: string;
+}
+
+export interface AgrarmonitorRegisterResultDto {
+  success: boolean;
+  message: string;
+}
+
+@Injectable()
+export class AgrarmonitorService {
+  private readonly logger = new Logger(AgrarmonitorService.name);
+  private client: AgrarmonitorConnectorResult | null = null;
+
+  constructor(private readonly configService: ConfigService) {}
+
+  async getClient(): Promise<AgrarmonitorConnectorResult> {
+    if (this.client) return this.client;
+
+    const username = this.configService.get<string>('AGRARMONITOR_USERNAME', '');
+    const password = this.configService.get<string>('AGRARMONITOR_PASSWORD', '');
+    const baseUrl = this.configService.get<string>('AGRARMONITOR_BASE_URL', 'https://admin7.agrarmonitor.de');
+    const apiBaseUrl = this.configService.get<string>('AGRARMONITOR_API_BASE_URL', 'https://api.agrarmonitor.de');
+    const apiToken = this.configService.get<string>('AGRARMONITOR_API_TOKEN');
+    const cookiePath = this.configService.get<string>('AGRARMONITOR_COOKIE_PATH', './data/agrarmonitor-cookies.json');
+    const encryptionKey = this.configService.get<string>('AGRARMONITOR_ENCRYPTION_KEY');
+
+    const encryptor = encryptionKey ? new AesGcmCookieEncryptor(encryptionKey) : undefined;
+    const cookieStore = new FileCookieStore(cookiePath, { encryptor, logger: this.logger });
+
+    this.client = await createAgrarmonitorClient({
+      baseUrl,
+      apiBaseUrl,
+      apiToken,
+      username,
+      password,
+      cookieStore,
+      autoLogin: true,
+      autoRetry: true,
+      logger: this.logger,
+    });
+
+    return this.client;
+  }
+
+  async getStatus(): Promise<AgrarmonitorStatusDto> {
+    try {
+      const client = await this.getClient();
+      const [registrierungStatus, freigeschaltetStatus] = await Promise.all([
+        client.checkRegistriert(),
+        client.checkFreigeschaltet(),
+      ]);
+      return {
+        connected: true,
+        registriert: registrierungStatus.registriert,
+        freigeschaltet: freigeschaltetStatus.freigeschaltet,
+      };
+    } catch (err: any) {
+      this.client = null;
+      return {
+        connected: false,
+        registriert: null,
+        freigeschaltet: null,
+        error: err?.message ?? 'Verbindung fehlgeschlagen',
+      };
+    }
+  }
+
+  async registerDevice(pcName: string, agrarmonitorId: string): Promise<AgrarmonitorRegisterResultDto> {
+    const client = await this.getClient();
+    const result = await client.registerDevice({ agrarmonitorId, pcName });
+    return { success: result.success, message: result.message };
+  }
+}