fix: ensure Redis Tag version operator uses string values

Convert version parameter to string for Redis Tag operator compatibility.
The Redis Tag operator requires string values for comparison operations.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: bsbodden

langgraph/checkpoint/redis/__init__.py

@@ -539,7 +539,7 @@ def get_channel_values(
                 filter_expression=(Tag("thread_id") == storage_safe_thread_id)
                 & (Tag("checkpoint_ns") == storage_safe_checkpoint_ns)
                 & (Tag("channel") == channel)
-                & (Tag("version") == version),
+                & (Tag("version") == str(version)),
                 return_fields=["type", "$.blob"],
                 num_results=1,
             )

langgraph/checkpoint/redis/aio.py

@@ -957,7 +957,7 @@ async def aget_channel_values(
                 filter_expression=(Tag("thread_id") == storage_safe_thread_id)
                 & (Tag("checkpoint_ns") == storage_safe_checkpoint_ns)
                 & (Tag("channel") == channel)
-                & (Tag("version") == version),
+                & (Tag("version") == str(version)),
                 return_fields=["type", "$.blob"],
                 num_results=1,
             )

langgraph/checkpoint/redis/ashallow.py

@@ -629,7 +629,7 @@ async def aget_channel_values(
                 filter_expression=(Tag("thread_id") == thread_id)
                 & (Tag("checkpoint_ns") == checkpoint_ns)
                 & (Tag("channel") == channel)
-                & (Tag("version") == version),
+                & (Tag("version") == str(version)),
                 return_fields=["type", "$.blob"],
                 num_results=1,
             )

langgraph/checkpoint/redis/shallow.py

@@ -641,7 +641,7 @@ def get_channel_values(
                 filter_expression=(Tag("thread_id") == thread_id)
                 & (Tag("checkpoint_ns") == checkpoint_ns)
                 & (Tag("channel") == channel)
-                & (Tag("version") == version),
+                & (Tag("version") == str(version)),
                 return_fields=["type", "$.blob"],
                 num_results=1,
             )