feat(backend): Datenexport-Modul (Modul 21)

ExportModule mit GET /export/colonies.csv, /export/honey-batches.csv,
/export/:entity.json (apiaries/colonies/queens/honey-batches/tasks)
und /export/:report.pdf (honey-batch-traceability via pdfkit).
Ausserdem fehlendes "typecheck"-Skript in package.json ergaenzt
(von CLAUDE.md dokumentiert, war aber nicht vorhanden).

ApiCore-Backend/package.json

@@ -13,6 +13,7 @@
     "start:debug": "nest start --debug --watch",
     "start:prod": "node dist/main",
     "lint": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
+    "typecheck": "tsc --noEmit",
     "test": "jest",
     "test:watch": "jest --watch",
     "test:cov": "jest --coverage",
@@ -36,6 +37,7 @@
     "helmet": "^8.3.0",
     "passport": "^0.7.0",
     "passport-jwt": "^4.0.1",
+    "pdfkit": "^0.19.1",
     "reflect-metadata": "^0.2.2",
     "rxjs": "^7.8.1"
   },
@@ -51,6 +53,7 @@
     "@types/jest": "^30.0.0",
     "@types/node": "^24.0.0",
     "@types/passport-jwt": "^4.0.1",
+    "@types/pdfkit": "^0.17.6",
     "@types/supertest": "^7.0.0",
     "eslint": "^9.18.0",
     "eslint-config-prettier": "^10.0.1",