feat: add website social link, fix herkunft origin display, GUI backup schedule, and format-based batch numbering

- SiteSettings gains websiteUrl (e.g. online shop link) alongside the
  existing social links, editable in Verwaltung > Automatisierung.
- /herkunft/[lot] now shows the apiary's Standort instead of its internal
  Name (so multiple apiaries at one location read as one origin), adds
  small icons per social link, and surfaces previously-fetched-but-unused
  data (Honigsorte, Abfülldatum, stat cards) to make the page a richer
  customer-facing info page.
- Backup schedule (path/cron/retention) is now also configurable via the
  GUI (Verwaltung > Backup), stored in a new BackupSettings singleton;
  an env var always wins over the GUI value per field, and the scheduler
  reloads its cron job live when GUI settings change.
- New Automatisierung rules let an admin define a format (e.g.
  "WH-{YYYY}-{SEQ:4}") that auto-generates HoneyBatch.batchNumber and
  BottlingBatch.lotNumber on creation, with an atomic per-rule sequence
  counter and a manual reset. Manual entry still works when the rule is
  inactive.

ApiCore-Backend/src/site-settings/dto/update-site-settings.dto.ts

@@ -25,4 +25,11 @@ export class UpdateSiteSettingsDto {
   @IsUrl({ require_protocol: true })
   @MaxLength(300)
   tiktokUrl?: string;
+
+  @ApiPropertyOptional({ description: 'Leerer String löscht den Link' })
+  @IsOptional()
+  @ValidateIf((_, value: string) => value !== '')
+  @IsUrl({ require_protocol: true })
+  @MaxLength(300)
+  websiteUrl?: string;
 }

ApiCore-Backend/src/site-settings/site-settings.service.spec.ts

@@ -18,6 +18,7 @@ describe('SiteSettingsService', () => {
     youtubeUrl: 'https://youtube.com/@wabenhain',
     instagramUrl: null as string | null,
     tiktokUrl: null as string | null,
+    websiteUrl: null as string | null,
     updatedAt: new Date('2026-01-01'),
   };
 
@@ -84,6 +85,7 @@ describe('SiteSettingsService', () => {
           youtubeUrl: undefined,
           instagramUrl: 'https://instagram.com/wabenhain',
           tiktokUrl: undefined,
+          websiteUrl: undefined,
         },
       });
       expect(result.instagramUrl).toBe('https://instagram.com/wabenhain');
@@ -111,6 +113,7 @@ describe('SiteSettingsService', () => {
           youtubeUrl: null,
           instagramUrl: undefined,
           tiktokUrl: undefined,
+          websiteUrl: undefined,
         },
       });
     });
@@ -127,6 +130,7 @@ describe('SiteSettingsService', () => {
           youtubeUrl: undefined,
           instagramUrl: undefined,
           tiktokUrl: undefined,
+          websiteUrl: undefined,
         },
       });
     });

ApiCore-Backend/src/site-settings/site-settings.service.ts

@@ -48,6 +48,10 @@ export class SiteSettingsService {
             : undefined,
         tiktokUrl:
           dto.tiktokUrl !== undefined ? emptyToNull(dto.tiktokUrl) : undefined,
+        websiteUrl:
+          dto.websiteUrl !== undefined
+            ? emptyToNull(dto.websiteUrl)
+            : undefined,
       },
     });
     await this.auditLog.record({