Polars: py-0.19.12-rc.1 Release

⚠️ Deprecations

• Deprecate shift_and_fill in favor of shift (#11955)
• Deprecate clip_min/clip_max in favor of clip (#11961)

🚀 Performance improvements

• fix regression non-null asof join (#11984)
• drasticly improve performance of limit on async parquet datasets (#11965)

✨ Enhancements

• optimize asof_join and allow null/string keys (#11712)
• limit concurrent downloads in async parquet (#11971)
• sample fraction can take an expr (#11943)
• Add infer_schema_length to pl.read_json (#11724)

🐞 Bug fixes

• fix streaming multi-column/multi-dtype sort (#11981)
• ensure streaming parquet datasets deal with limits (#11977)
• implement proper hash for identifier in cse (#11960)
• fix take return dtype in group context. (#11949)
• fix panic in format of anonymous scans (#11951)
• sql In should work without specific ops (#11947)
• construct list series from any values subject to dtype (#11944)

🛠️ Other improvements

• optimize asof_join and allow null/string keys (#11712)
• Add Development and Releases sections to the documentation (#11932)
• include the "build" dir when running make clean for docs (#11970)
• make cloning PyExpr consistent (#11956)
• fix take return dtype in group context. (#11949)
• warn about scan_pyarrow_dataset's limitations and suggest scan_parquet instead (if possible) (#11952)
• Add set_fmt_table_cell_list_len to API docs (#11942)

Thank you to all our contributors for making this release possible! @MarcoGorelli, @Rohxn16, @alexander-beedie, @messense, @orlp, @reswqa, @ritchie46, @squnit and @stinodego