* proposal: meta field ranker
* Apply suggestions from code review
Co-authored-by: ZanSara <sarazanzo94@gmail.com>
* update proposal filename
* feat: add metafield ranker
* fix docstrings
* remove proposal file from pr
* add release notes
* update code according to new Document class
* separate loops for each ranking mode in __merge_scores
* change error type in init and new tests for linear score warning
* docstring upd
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Co-authored-by: ZanSara <sarazanzo94@gmail.com>
Co-authored-by: Daria Fokina <daria.fokina@deepset.ai>
