fix(agents-api): Add limit to kNN search. Update search_docs_by_embed…

…ding.py (#761)

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> [!IMPORTANT]
> Adds a limit to kNN search in `search_docs_by_embedding` to enhance
diversity based on `mmr_strength`.
> 
>   - **Behavior**:
> - Adds a limit to kNN search in `search_docs_by_embedding` to retrieve
`k*(3 if mmr_strength else 1)` candidates for diversity.
> - Adjusts the limit in both the `search_query` and
`normal_interim_query` sections.
>   - **Misc**:
>     - Updates comments to reflect the new limit logic.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=julep-ai%2Fjulep&utm_source=github&utm_medium=referral)<sup>
for edc471d. It will automatically
update as commits are pushed.</sup>

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agents-api/agents_api/models/docs/search_docs_by_embedding.py

@@ -213,6 +213,8 @@ def search_docs_by_embedding(
                 distance = cos_dist(query, embedding),
                 distance <= {radius}
 
+            :limit {k*(3 if mmr_strength else 1)}   # Get more candidates for diversity
+
             :create _search_result {{
                 doc_id,
                 index,
@@ -244,7 +246,7 @@ def search_docs_by_embedding(
 
         # Sort the results by distance to find the closest matches
         :sort -mmr_score
-        :limit {k}
+        :limit {k*(3 if mmr_strength else 1)}   # Get more candidates for diversity
 
         :create _interim {{
             owner_type,