Add support for External Memory (the future replacement for UserMemory) (#2510)

* fix: surfacing properly supported types by Mem0Storage

* feat: prepare Mem0Storage to accept config paramenter

We're planning to remove `memory_config` soon. This commit kindly prepare this storage to accept the config provided directly

* feat: add external memory

* fix: cleanup Mem0 warning while adding messages to the memory

* feat: support set the current crew in memory

This can be useful when a memory is initialized before the crew, but the crew might still be a very relevant attribute

* fix: allow to reset only an external_memory from crew

* test: add external memory test

* test: ensure the config takes precedence over memory_config when setting mem0

* fix: support to provide a custom storage to External Memory

* docs: add docs about external memory

* chore: add warning messages about the deprecation of UserMemory

* fix: fix typing check

---------

Co-authored-by: Lorenze Jay <63378463+lorenzejay@users.noreply.github.com>

src/crewai/memory/external/external_memory_item.py

@@ -0,0 +1,13 @@
+from typing import Any, Dict, Optional
+
+
+class ExternalMemoryItem:
+    def __init__(
+        self,
+        value: Any,
+        metadata: Optional[Dict[str, Any]] = None,
+        agent: Optional[str] = None,
+    ):
+        self.value = value
+        self.metadata = metadata
+        self.agent = agent