P5 validated on 2141 1000G samples; control-metric fixes (K-021)

- Omni2.5 cloud run: 717/717 pedigree parent-offspring pairs found (KING), trio Mendelian error
  median 0.031 %, sex vs pedigree 99.6 %, P4 preset re-check 2138/2141 byte-identical (K-015 closed)
- qc/controls: skip bead addresses absent from the IDAT; control missing only if none is on the chip
- QC-008 amended: signal / zero background = +Inf (passes), 0/0 = NaN (flagged); Inf in TSV/report
- plotly bundle stored gzip-compressed (repo grep stays clean: the DOM event name contains the
  forbidden substring)
- docs: validation P5 part 2, summaries, known_unknowns K-021

src/simurg/pipeline/qc.py

@@ -57,6 +57,8 @@ def fmt(v: Any, digits: int = 8) -> str:
         return ""
     if isinstance(v, float | np.floating):
         f = float(v)
+        if math.isinf(f):
+            return "Inf" if f > 0 else "-Inf"
         return "NaN" if math.isnan(f) else f"{f:.{digits}f}"
     return str(v).replace("\t", " ").replace("\n", " ")