## Summary
- Fix `name in db` and `len(db)` for local Python connections with more
than one page of tables.
- Use `list_tables()` pagination instead of deprecated `table_names()`
with its default 10-item page.
- Add regression coverage with 20 tables so later pages are included.
Fixes#2727.
## Validation
- `python3 -m py_compile python/python/lancedb/db.py
python/python/tests/test_db.py`
- No-build Python harness that extracts and executes the edited
`LanceDBConnection` pagination methods: passed
- `uvx ruff check python/python/lancedb/db.py
python/python/tests/test_db.py`
- `uvx ruff format --check python/python/lancedb/db.py
python/python/tests/test_db.py`
Note: `uv run pytest
python/tests/test_db.py::test_db_contains_and_len_include_all_table_name_pages
-q` was attempted first, but it stayed in the broad Rust/PyO3 native
extension build and was stopped before pytest started.
