Support Metadata of RedisAutoConfiguration for indexing

[yaner-here]

Close #6308

This PR allows developers to configure metadata for RedisAutoConfiguration like this:

spring:
  ai:
    vectorstore:
      redis:
        initialize-schema: true
        metadata-fields:
          - name: country
            type: tag
          - name: year
            type: numeric
          - name: description
            type: text

RedisVectorStore only supports three types: TAG, NUMERIC and TEXT. This PR only supports them as well, without out GEO and VECTOR defined in edis.clients.jedis.search.Schema.FieldType.

spring-ai/vector-stores/spring-ai-redis-store/src/main/java/org/springframework/ai/vectorstore/redis/RedisVectorStore.java

Line 94 in c52f675

* <li>Flexible metadata field types (TEXT, TAG, NUMERIC) for advanced filtering</li>

https://github.com/redis/jedis/blob/33fc911a2aa01e93fa4bb2e0caae72e85a26ec4e/src/main/java/redis/clients/jedis/search/Schema.java#L16-L24