[C++][Python] Support reading/writing key-value metadata from/to ColumnChunkMetaData

[clee704]

Describe the enhancement requested

According to the standard, ColumnMetaData can have key_value_metadata which is a list of KeyValue.

https://parquet.apache.org/docs/file-format/metadata/

Component(s)

C++

[mapleFU]

Issue resolved by pull request 41580
#41580