[Docs] Added MongoDB persistence in how-tos (#960)

---------

Co-authored-by: Vadym Barda <vadim.barda@gmail.com>
Co-authored-by: Vadym Barda <vadym@langchain.dev>

docs/_scripts/copy_notebooks.py

@@ -29,6 +29,7 @@ _MANUAL = {
         "memory/delete-messages.ipynb",
         "memory/add-summary-conversation-history.ipynb",
         "persistence_postgres.ipynb",
+        "persistence_mongodb.ipynb",
         "visualization.ipynb",
         "state-model.ipynb",
         "subgraph.ipynb",

docs/docs/how-tos/index.md

@@ -26,6 +26,7 @@ LangGraph makes it easy to persist state across graph runs. The guide below show
 - [How to delete messages](memory/delete-messages.ipynb)
 - [How to add summary conversation memory](memory/add-summary-conversation-history.ipynb)
 - [How to create a custom checkpointer using Postgres](persistence_postgres.ipynb)
+- [How to create a custom checkpointer using MongoDB](persistence_mongodb.ipynb)
 
 ## Human in the Loop
 

docs/mkdocs.yml

@@ -137,6 +137,7 @@ nav:
           - Delete messages: how-tos/memory/delete-messages.ipynb
           - Add summary of the conversation history: how-tos/memory/add-summary-conversation-history.ipynb
           - Create custom checkpointer using Postgres: how-tos/persistence_postgres.ipynb
+          - Create custom checkpointer using MongoDB: how-tos/persistence_mongodb.ipynb
       - Human-in-the-loop:
           - Add breakpoints: how-tos/human_in_the_loop/breakpoints.ipynb
           - Wait for user input: how-tos/human_in_the_loop/wait-user-input.ipynb