feat(10-03): search, sort, filter, page and bulk-delete any list

- List state (search, sort, dir, page, per_page, filter[<name>]) lives in
  the URL query through parseListQuery/toListQuery; every change is a
  router replace and clears the selection; search is debounced 300 ms and
  resets the page
- DataTable renders the schema columns with a tri-state page checkbox,
  asc/desc/none sorting with aria-sort, selected rows, a sticky header,
  eight skeleton rows while loading and an empty slot
- CellValue renders text (muted dash when empty, arrays comma-joined),
  datetime as YYYY-MM-DD HH:mm and switch as the Tak/Nie pills
- The heading shows the plural recordCount and the create button;
  delete sits in the toolbar, disabled without a selection, and confirms
  with the plural deleteConfirm in a Reka alert dialog before POSTing
  bulk-delete; a 409 shows a danger toast
- FilterBar renders switch (JSON of the option value), daterange
  (from..to) and scope filters (choices from filters/{scope}/options)
- Pagination shows the range, the per-page select over perPageOptions
  (hidden with one choice) and a pager with ellipsis
- The tracer smoke test skips the new checkbox column; new backend::lang
  list keys; boardwalk/dist rebuilt

admin/tests/fixtures/lang.json

@@ -117,12 +117,27 @@
     "backend::lang.list.column_updated": {
       "other": "Zaktualizowano"
     },
+    "backend::lang.list.delete_failed": {
+      "other": "Nie udało się usunąć zaznaczonych rekordów."
+    },
     "backend::lang.list.delete_selected": {
       "other": "Usuń zaznaczone"
     },
     "backend::lang.list.empty_value": {
       "other": "—"
     },
+    "backend::lang.list.filter_all": {
+      "other": "Wszystkie"
+    },
+    "backend::lang.list.filter_from": {
+      "other": "Od"
+    },
+    "backend::lang.list.filter_to": {
+      "other": "Do"
+    },
+    "backend::lang.list.filters": {
+      "other": "Filtry"
+    },
     "backend::lang.list.load_failed": {
       "other": "Nie udało się wczytać listy."
     },
@@ -138,6 +153,9 @@
     "backend::lang.list.no_results": {
       "other": "0 wyników"
     },
+    "backend::lang.list.pagination": {
+      "other": "Stronicowanie"
+    },
     "backend::lang.list.pagination_range": {
       "other": ":from–:to z :total"
     },
@@ -153,6 +171,9 @@
       "many": ":count wyników",
       "other": ":count wyniku"
     },
+    "backend::lang.list.search": {
+      "other": "Szukaj"
+    },
     "backend::lang.list.search_prompt": {
       "other": "Szukaj…"
     },