v0.1.3 Review fixes

• Fix TCO sentinel leak, optimizer node rebuilds and non-finite constant folds
• Fix descending sort stability, $pad allocation and quadratic group-by
• Fix argument packing for array arguments and $eval scoping
• Fix array-constructor stages, chain invocation and transform delete
• Re-measure the comparison benchmark and update docs (61x)
• Bump version to 0.1.3