feat: Display candidate name from CV data instead of filename

- Added CandidateName field to CVCheckDto
- Extract candidate name from ReportJson or ExtractedDataJson
- Dashboard now shows actual candidate name for JSON uploads
- PDF export uses candidate name from report

This fixes the issue where JSON files showed their filename (e.g.,
"CLEAN-001") instead of the actual candidate name from the CV data.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/RealCV.Web/Components/Pages/Dashboard.razor

@@ -210,7 +210,7 @@
                                             </svg>
                                         </div>
                                         <div>
-                                            <p class="mb-0 fw-semibold text-dark">@Path.GetFileNameWithoutExtension(check.OriginalFileName)</p>
+                                            <p class="mb-0 fw-semibold text-dark">@(!string.IsNullOrEmpty(check.CandidateName) ? check.CandidateName : Path.GetFileNameWithoutExtension(check.OriginalFileName))</p>
                                             <small class="text-muted">@Path.GetExtension(check.OriginalFileName).ToUpperInvariant()</small>
                                         </div>
                                     </div>
@@ -659,7 +659,7 @@
 
                 reportDataList.Add(new RealCV.Web.Services.PdfReportData
                 {
-                    CandidateName = Path.GetFileNameWithoutExtension(check.OriginalFileName) ?? "Unknown",
+                    CandidateName = report.CandidateName ?? Path.GetFileNameWithoutExtension(check.OriginalFileName) ?? "Unknown",
                     UploadDate = check.CreatedAt,
                     Score = report.OverallScore,
                     ScoreLabel = report.ScoreLabel,