cli: set verbose flag for pull in langgraph build (#955)

* Set verbose flag for langgraph build.

* Update CLI README.

libs/cli/README.md

@@ -1,3 +1,10 @@
 # langchain-cli
 
-This package implements the official CLI for LangGraph API.
+This package implements the official CLI for LangGraph API.
+
+## How to Test CLI Changes Locally
+These instructions are for CLI development and testing. Use the CLI examples to test CLI changes locally.
+1. Make changes to the CLI code.
+1. Navigate to the `libs/cli/examples`: `cd libs/cli/examples`
+1. Install CLI examples dependencies: `poetry install`
+1. Run/test CLI command (e.g. `langgraph build`).

libs/cli/langgraph_cli/cli.py

@@ -369,6 +369,7 @@ def _build(
                 "docker",
                 "pull",
                 f"{base_image}:{config_json['python_version']}",
+                verbose=True,
             )
         )
     set("Building...")