Ignore Python bytecode in the backend tree

Why: House-style tests write __pycache__ next to the skill source. Those
files must stay out of later commits, not only be deleted once.

Evidence: .gitignore lists __pycache__/ and *.pyc.

Impact: Local test runs no longer show bytecode as untracked files.

Refs: feature/agent-professional-deliverables
Co-authored-by: Cursor <cursoragent@cursor.com>

.gitignore

@@ -6,3 +6,5 @@
 web/dist/*
 !web/dist/.gitkeep
 data/
+__pycache__/
+*.pyc