chore: auto-commit (97 archivos)

- .claude/CLAUDE.md
- .claude/agents/fn-recopilador/SKILL.md
- .claude/rules/INDEX.md
- .claude/rules/cpp_apps.md
- bash/functions/infra/build_cpp_windows.sh
- cpp/CMakeLists.txt
- cpp/PATTERNS.md
- cpp/framework/app_base.cpp
- cpp/framework/app_base.h
- dev/issues/README.md
- ...

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

functions/datascience/metrics_drift.go

@@ -0,0 +1,29 @@
+package datascience
+
+import "sort"
+
+// MetricsDrift calculates the relative drift of a current measurement against
+// a historical baseline computed at the given percentile.
+//
+// historical is a window of past measurements (e.g. duration_ms, bytes).
+// percentile selects the baseline: 0.5 = median, 0.95 = p95.
+// drift = (current - baseline) / baseline, e.g. 0.47 means +47% above baseline.
+//
+// Returns drift=0, baseline=0 when historical is empty or baseline is zero.
+func MetricsDrift(historical []int64, current int64, percentile float64) (drift float64, baseline int64) {
+	if len(historical) == 0 {
+		return 0, 0
+	}
+
+	sorted := make([]int64, len(historical))
+	copy(sorted, historical)
+	sort.Slice(sorted, func(i, j int) bool { return sorted[i] < sorted[j] })
+
+	baseline = Percentile(sorted, percentile)
+	if baseline == 0 {
+		return 0, 0
+	}
+
+	drift = float64(current-baseline) / float64(baseline)
+	return drift, baseline
+}