chore: auto-commit (57 archivos)

- frontend/functions/core/format_datetime_short.md
- frontend/functions/core/format_datetime_short.test.ts
- frontend/functions/core/format_datetime_short.ts
- frontend/functions/core/format_duration.md
- frontend/functions/core/format_duration.test.ts
- frontend/functions/core/format_duration.ts
- frontend/functions/core/month_grid.md
- frontend/functions/core/month_grid.test.ts
- frontend/functions/core/month_grid.ts
- frontend/functions/core/string_hash_palette.md
- ...

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

functions/datascience/percentile_int64.go

@@ -0,0 +1,19 @@
+package datascience
+
+// Percentile returns the value at percentile p (0.0–1.0) from a pre-sorted
+// ascending slice of int64 values.
+// Returns 0 for an empty slice.
+// idx is computed as int(float64(len-1)*p), clamped to [0, len-1].
+func Percentile(sorted []int64, p float64) int64 {
+	if len(sorted) == 0 {
+		return 0
+	}
+	idx := int(float64(len(sorted)-1) * p)
+	if idx < 0 {
+		idx = 0
+	}
+	if idx >= len(sorted) {
+		idx = len(sorted) - 1
+	}
+	return sorted[idx]
+}