Unbind cudf::size_type from offsets used by list columns - #23607

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@cpp/include/cudf/detail/sizes_to_offsets_iterator.cuh`:
- Around line 289-292: Update the final STRING-offset construction in
ngrams_tokenize to call cudf::strings::detail::make_offsets_child_column instead
of the generic sizes-to-offsets helper, preserving the configured dynamic offset
type and allowing large-string totals. Keep the existing tokenization and offset
values unchanged.
- Around line 321-322: Prevent oversized cudf::size_type values from wrapping
before validation: in the generic path around the device lambda in
sizes_to_offsets_iterator.cuh, keep the scan input wide and perform the checked
int32_t conversion only after validating against total_elements; in
cpp/include/cudf/lists/detail/scatter.cuh lines 234-239, replace the direct
lv->view().size() narrowing with a checked int32_t step and preserve the
existing range-validation behavior.

In `@cpp/src/groupby/sort/group_collect.cu`:
- Around line 88-94: Enforce checked INT32 range handling for LIST offsets at
all four sites: in cpp/src/groupby/sort/group_collect.cu lines 88-94, validate
every group_offsets value before copying into the INT32 offsets column; in
cpp/include/cudf_test/column_wrapper.hpp lines 1614-1629, validate cumulative
nested child sizes before int32_t conversion; in
cpp/include/cudf_test/column_wrapper.hpp lines 1669-1675, validate c->size()
before constructing the INT32 offsets column; and in
cpp/src/io/utilities/column_buffer.cpp lines 107-110, reject or safely
checked-convert oversized string offsets before creating the LIST column. Ensure
no conversion can wrap or produce invalid memory access.

In `@cpp/src/lists/combine/concatenate_rows.cu`:
- Around line 108-116: Guard every size_type-to-int32_t LIST offset conversion:
in cpp/src/lists/combine/concatenate_rows.cu lines 108-116, accumulate into a
wider temporary and reject cumulative child counts above INT32_MAX before the
exclusive scan; in cpp/src/lists/copying/concatenate.cu lines 66-72, accumulate
shift in a wide type, validate its range, and return an explicit int32_t from
the device transform; in cpp/src/io/json/host_tree_algorithms.cu line 216,
validate row_offsets before scattering and use an int32-compatible scan; in
cpp/src/lists/utilities.cu lines 35-38, ensure labels_to_offsets rejects
label-derived values outside the int32_t range.

In `@cpp/src/lists/copying/copying.cu`:
- Around line 43-45: Keep LIST offset storage explicitly int32_t at all affected
sites: in cpp/src/lists/copying/copying.cu lines 43-45, allocate out_offsets as
rmm::device_uvector<int32_t>; in
cpp/src/lists/combine/concatenate_list_elements.cu lines 50-52, create the
empty-inner-child fallback with int32_t zero offsets; and in
cpp/src/io/json/parser_features.cpp line 78, use a LIST-specific int32_t
zero-offset helper while leaving string offsets unchanged.

In `@cpp/src/lists/sequences.cu`:
- Line 159: Update the internal LIST offset pointer declarations in
tabulator::offsets, sequences_dispatcher::operator(), and
sequences_functor::invoke from size_type const* to int32_t const*. Preserve
size_type for row counts and element indices so LIST offsets remain independent
of cudf::size_type.

In `@java/src/main/native/src/ColumnViewJni.cu`:
- Around line 182-183: Update the generate_list_offsets implementation to read
the validated INT32 list_length input using int32_t iterators, replacing the
cudf::size_type begin/end iterator types while preserving the existing
offset-generation logic.

---

Outside diff comments:
In `@cpp/src/groupby/sort/group_collect.cu`:
- Around line 66-70: Declare explicit return types on both changed device
lambdas passed to device algorithms: in cpp/src/groupby/sort/group_collect.cu
lines 66-70, make the lambda returning the null-count result return size_type;
in cpp/src/rolling/detail/rolling_collect_list.cu lines 61-65, make the
corresponding lambda return bool.

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@cpp/src/quantiles/tdigest/tdigest.cu`:
- Line 362: In cpp/src/quantiles/tdigest/tdigest.cu at lines 362-362, reject
input.size() == INT32_MAX before allocating input.size() + 1 offsets; for
non-empty output, compute input.size() * percentiles.size() in a widened type
and reject values above INT32_MAX before num_output_values, grid sizing, and
exclusive scan. In cpp/src/strings/search/find_multiple.cu at lines 72-73,
reject strings_count == INT32_MAX before evaluating strings_count + 1, while
preserving the existing product check for the final offset.

---

Nitpick comments:
In `@cpp/src/quantiles/tdigest/tdigest_util.cuh`:
- Line 18: Update the header containing the t-digest offsets declaration to
directly include the standard <cstdint> header before using int32_t, without
relying on transitive includes.