fix: distinguish user-provided mapping from auto-created default in summary

Check userMappingFile (the CLI argument) instead of importOptions.UserMappings
to determine if the user provided a mapping file. When --strip-owner-fields is
used without --user-mapping, the code creates an auto-default mapping that
should not report "userMappingProvided": true.

Closes #202

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: joshsmithxrm

src/PPDS.Cli/Commands/Data/ImportCommand.cs

@@ -294,7 +294,7 @@ private static async Task<int> ExecuteAsync(
                         ImportMode = importOptions.Mode.ToString(),
                         StripOwnerFields = importOptions.StripOwnerFields,
                         BypassPlugins = importOptions.BypassCustomPlugins != CustomLogicBypass.None,
-                        UserMappingProvided = importOptions.UserMappings != null
+                        UserMappingProvided = userMappingFile != null
                     };
 
                     await outputManager.WriteSummaryAsync(