fix: staticcheck S1016 struct conversion + Helm with/else-if parse error

- Use type conversion DigestStatusCount(c) instead of struct literal
- Replace with...else-if (invalid in Go templates) with if...else-if chain
- Add *.bak and cmd/agent/*.key/*.pem to .gitignore

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/service/digest.go

@@ -122,10 +122,7 @@ func (s *DigestService) GenerateDigest(ctx context.Context) (*DigestData, error)
 		s.logger.Warn("failed to get status counts for digest", "error", err)
 	} else if counts, ok := statusRaw.([]CertificateStatusCount); ok {
 		for _, c := range counts {
-			digest.StatusCounts = append(digest.StatusCounts, DigestStatusCount{
-				Status: c.Status,
-				Count:  c.Count,
-			})
+			digest.StatusCounts = append(digest.StatusCounts, DigestStatusCount(c))
 		}
 	}