[INFO] Reading target VCF: HCC1395_BL.GERMLINE.merged.vcf.gz
[INFO] Reading source VCF: chip_pon.chip_pon.harmonized.vcf.gz
[INFO] Adding header fields with prefix 'CHIP_PON' for: FRACTION
[INFO] Building source variant lookup...
[INFO] Found 365410 variants in source VCF
[INFO] Processing target variants and merging characteristics...
[INFO] Complete! Processed 254 variants, matched 196 (77.2%)
[SUCCESS] VCF merging completed successfully!