added knowledge to agent level (#1655)

* added knowledge to agent level

* linted

* added doc

* added from suggestions

* added test

* fixes from discussion

* fix docs

* fix test

* rm cassette for knowledge_sources test as its a mock and update agent doc string

* fix test

* rm unused

* linted

src/crewai/knowledge/utils/knowledge_utils.py

@@ -0,0 +1,12 @@
+from typing import Any, Dict, List
+
+
+def extract_knowledge_context(knowledge_snippets: List[Dict[str, Any]]) -> str:
+    """Extract knowledge from the task prompt."""
+    valid_snippets = [
+        result["context"]
+        for result in knowledge_snippets
+        if result and result.get("context")
+    ]
+    snippet = "\n".join(valid_snippets)
+    return f"Additional Information: {snippet}" if valid_snippets else ""