FFPE deamination QC pipeline

- ffpe_damage_v2.py: normalized C>T/G>A profiling (all 12 substitutions,
  R1/R2 and strand profiles, 5'/3' read-end distance, BED tracks, plots)
- ffpe_compare.py: low/moderate/high classification vs control samples
- make_test_data.py: synthetic BAM with known damage for validation

.gitignore

@@ -0,0 +1,5 @@
+.venv/
+__pycache__/
+*.pyc
+test_data/
+FFPE_QC/