docs: rename the native provider to @soulcraft/cor across public docs and JSDoc

The 3.0 native engine ships as @soulcraft/cor (brainy 8.x <-> cor 3.x are a
version-matched pair); the old @soulcraft/cortex package stays on the 2.x/7.x
line. Public docs and .d.ts-visible comments now name the correct package.
Historical 2.x contract references (e.g. the 2.3.1 read-side fallback) keep
the old name deliberately.

src/aggregation/AggregationIndex.ts

@@ -269,7 +269,7 @@ function recomputeMinMaxFromCounts(state: MetricState): void {
 /**
  * Exact percentile over a value multiset, using linear interpolation between closest ranks
  * (numpy 'linear' / type-7): `rank = p·(n−1)`, interpolating between the floor and ceil
- * positions of the sorted expansion. Mirrors Cortex's `MetricState::percentile` bit-for-bit.
+ * positions of the sorted expansion. Mirrors Cor's `MetricState::percentile` bit-for-bit.
  */
 function computePercentile(valueCounts: Record<string, number>, count: number, p: number): number {
   if (count === 0) return 0