VectorStore search filters doesn't support multiple $like/$ilike/$in/$nin on same column

[CXmartins]

When performing a search with filters that have multiple values for the same column, the current implementation only keeps the value for the last filter instance.

Example of a filter that fails:
{"$and": [{"code": {"$like": "WH00%"}}, {"code": {"$like": "EC00%"}}]}

current implementation keeps saves the params for ilike with the key column_name_ilike, thus with a random id only keeps the last value for each given column. In the example above would be {"code_ilike", "EC00%"}

Relevant code

• Ilike filter param return: https://github.com/langchain-ai/langchain-postgres/blob/main/langchain_postgres/v2/async_vectorstore.py#L1133
• Dict param update: https://github.com/langchain-ai/langchain-postgres/blob/main/langchain_postgres/v2/async_vectorstore.py#L1209