feat: qdrant generic client (#3377)

### Qdrant Client

* Add core client with collection, search, and document APIs (sync + async)
* Refactor utilities, types, and vector params (default 384-dim)
* Improve error handling with `ClientMethodMismatchError`
* Add score normalization, async embeddings, and optional `qdrant-client` dep
* Expand tests and type safety throughout

src/crewai/rag/core/exceptions.py

@@ -0,0 +1,26 @@
+"""Core exceptions for RAG module."""
+
+
+class ClientMethodMismatchError(TypeError):
+    """Raised when a method is called with the wrong client type.
+
+    Typically used when a sync method is called with an async client,
+    or vice versa.
+    """
+
+    def __init__(
+        self, method_name: str, expected_client: str, alt_method: str, alt_client: str
+    ) -> None:
+        """Create a ClientMethodMismatchError.
+
+        Args:
+            method_name: Method that was called incorrectly.
+            expected_client: Required client type.
+            alt_method: Suggested alternative method.
+            alt_client: Client type for the alternative method.
+        """
+        message = (
+            f"Method {method_name}() requires a {expected_client}. "
+            f"Use {alt_method}() for {alt_client}."
+        )
+        super().__init__(message)