Spring-ai Support poratlbe, filter expressions with AzureVectorStore

Support generic, portable metadata filters with AzureVectorStore. For example the:

vectorStore.similaritySearch(
   SearchRequest
      .query("The World")
      .withTopK(TOP_K)
      .withSimilarityThreshold(SIMILARITY_THRESHOLD)
      .withFilterExpression("country in ['UK', 'NL'] && year >= 2020"));

Internally will converted to the Azure Search OData filters like: $filter search.in(meta_country, 'UK,NL', ',') and meta_year ge 2020.

All portable operations are supported, but you have to list explicitly the metadata fields used in filter expression.

Comment From: markpollack

Moved into package org.springframework.ai.vectorstore.azure There are some other vector stores that need an additional level in their package name as different jars can't use the same package name.

Comment From: markpollack

merged as 69d6da2393abef7cdfe95a971f19903f3712a813