Improve documentation for Linear Top Level Normalizer (#134216)

* Improved changes to the doc

* Add back missing warning about avoiding 'none' normalizer with field grouping

* Move applies_to tag to specific behavior description to clarify version support

* cleaning it up

* cleaned up

* cleaned up

* Update linear-retriever.md

* Update docs/reference/elasticsearch/rest-apis/retrievers/linear-retriever.md

Co-authored-by: Liam Thompson <[email protected]>

* Update docs/reference/elasticsearch/rest-apis/retrievers/linear-retriever.md

Co-authored-by: Liam Thompson <[email protected]>

---------

Co-authored-by: Liam Thompson <[email protected]>

Author: mridula-s109

docs/reference/elasticsearch/rest-apis/retrievers/linear-retriever.md

@@ -36,11 +36,8 @@ Combining `query` and `retrievers` is not supported.
     Required when `query` is specified.
 
     When used with the [multi-field query format](../retrievers.md#multi-field-query-format) (`query` parameter), normalizes scores per [field grouping](../retrievers.md#multi-field-field-grouping).
-    Otherwise serves as the default normalizer for any sub-retriever that doesn't specify its own normalizer. Per-retriever normalizers always take precedence over the top-level normalizer.
 
-    :::{note}
-    **Top-level normalizer support for sub-retrievers**: The ability to use a top-level normalizer as a default for sub-retrievers was introduced in Elasticsearch 9.2+. In earlier versions, only per-retriever normalizers are supported.
-    :::
+    Otherwise this serves as the default normalizer for any sub-retriever that doesn't specify its own normalizer. Per-retriever normalizers always take precedence over the top-level normalizer. {applies_to}`stack: ga 9.2`
 
     ::::{warning}
     Avoid using `none` as that will disable normalization and may bias the result set towards lexical matches.
@@ -83,8 +80,7 @@ Each entry in the `retrievers` array specifies the following parameters:
 
     Specifies how the retriever's score will be normalized before applying the specified `weight`.
     See [normalizers](#linear-retriever-normalizers) for supported values.
-    If not specified, uses the top-level `normalizer` or defaults to `none` if no top-level normalizer is set.
-    {applies_to}`stack: ga 9.2`
+    If not specified, uses the top-level `normalizer` (9.2+) or defaults to `none` (earlier versions).
 
 See also [this hybrid search example](retrievers-examples.md#retrievers-examples-linear-retriever) using a linear retriever on how to independently configure and apply normalizers to retrievers.