Refactor worker to use config, DI, and Quartz scheduling

- Add WorkerSettings class and update appsettings for config-driven setup
- Integrate Quartz.NET for job scheduling (FinalizeDocumentJob, APIEnvelopeJob)
- Refactor Program.cs for DI of services (TempFileManager, PDFBurner, etc.)
- Implement TempFileManager for temp folder management and cleanup
- Rewrite Worker class for config validation, DB check, and lifecycle logging
- Update csproj to include Quartz and EnvelopeGenerator.Jobs references
- Improve maintainability, error handling, and logging throughout

EnvelopeGenerator.WorkerService/appsettings.json

@@ -4,5 +4,18 @@
       "Default": "Information",
       "Microsoft.Hosting.Lifetime": "Information"
     }
+  },
+  "WorkerSettings": {
+    "ConnectionString": "",
+    "Debug": false,
+    "IntervalMinutes": 1,
+    "PdfBurner": {
+      "IgnoredLabels": ["Date", "Datum", "ZIP", "PLZ", "Place", "Ort", "Position", "Stellung"],
+      "TopMargin": 0.1,
+      "YOffset": -0.3,
+      "FontName": "Arial",
+      "FontSize": 8,
+      "FontStyle": "Italic"
+    }
   }
 }