@gridkitjs/core v0.6.0

26adc6f: Added filtering infrastructure: FilterState/FilterEntry — a discriminated union of a %-wildcard text query, a typed exact-value match (type-scoped: a number never matches a string column), a custom predicate, or a nested GroupFilterEntry for AND/OR composition — ANDed together across top-level entries. Added the core filterRows / setColumnFilter / clearAllFilters / filterQueryFor / matchesQuery functions, and resolveShownRows, which composes filtering and sorting. Seed a grid's filter with defaultFilter on DataGridComponent. No header or toolbar UI ships yet — pre-filter dataSource yourself with the exported functions, or seed defaultFilter, until it does.
26adc6f: Added multi-column stacked sorting. A header's sort toggle cycles a column through ascending, descending, and off; Shift-click adds or updates a column in the stack instead of replacing it, sorted in priority order. Configure with sortableColumns / column.sortable, seed with defaultColumnSort, and listen with onColumnSortChange.