Allow to customize mappings parameters

[reta]

The request is coming from the Spring Data OpenSearch where we tried to add vector field type support. The previously introduced mappedTypeName allows to resolve mismatch between dense_vector type (Elasticsearch) and knn_vector (OpenSearch). However, the further troubles are coming from pretty much non-compatible parameters (dims vs dimensions, similarity vs space_type, ...).

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Closes #3254

[sothawo]

I won't find time before saturday to check this