chore: bump version to 3.13.6

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: bobmatnyc

src/gitflow_analytics/_version.py

@@ -1,4 +1,4 @@
 """Version information for gitflow-analytics."""
 
-__version__ = "3.13.5"
+__version__ = "3.13.6"
 __version_info__ = tuple(int(x) for x in __version__.split("."))