Upstream PR: lepture/mistune#456
Rendering an RST list item containing text and blockquotes could lose the previous-token state used by the renderer. That made separators inconsistent and exposed a prev lookup failure in the list item path.
RST list item rendering should behave like top-level RST rendering: non-blank child tokens need a stable prev relationship, and separate blockquotes should still be separated correctly.
render_list_item() now tracks prev between non-blank child tokens. RSTRenderer.block_quote() also treats block_text like paragraph for separator suppression, avoiding a spurious .. before the first quote inside a list item.
uv run --group dev python -m pytest tests/test_renderers.py -q-> 55 passeduv run --group dev python -m pytest -q-> 1112 passed, 3 subtests passeduv run --group dev ruff check src/mistune/renderers/_list.py src/mistune/renderers/rst.py tests/test_renderers.py-> passedgit diff --check-> passed