v2.26.2: fix Docker startup crash — data/ package excluded by .dockerignore

The data/ directory became a Python package (oui.py, patterns.py, satellites.py)
in v2.26.0, but .dockerignore still blanket-excluded it as runtime data.
This caused ModuleNotFoundError: No module named 'data.oui' on container startup.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.dockerignore

@@ -40,7 +40,11 @@ tasks/
 
 # Runtime data (mounted as volume)
 instance/
-data/
+
+# data/ is a Python package — only exclude non-code files
+data/*.json
+data/*.csv
+data/*.db
 
 # Build scripts
 build-multiarch.sh