chore: add example appsettings file

src/FiscalOS.API/appsettings.Example.json

@@ -0,0 +1,12 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*",
+  "AppDbContextOptions": {
+    "DatabaseFilePath": "DatabaseFilePath"
+  }
+}