chore: initialize repo with .gitignore

Excludes planning docs, Python artifacts, secrets, and runtime data.

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

.gitignore

@@ -0,0 +1,50 @@
+# Planning files
+docs/superpowers/
+
+# Python
+__pycache__/
+*.py[cod]
+*.pyo
+*.pyd
+.Python
+*.egg-info/
+dist/
+build/
+*.egg
+.eggs/
+
+# Virtual environments
+.venv/
+venv/
+env/
+
+# Environment / secrets
+.env
+*.env.local
+
+# Database
+*.db
+*.sqlite3
+
+# Logs
+*.log
+logs/
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Editor
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# Alembic (generated, not secrets — keep migrations in VCS but exclude caches)
+# (nothing to exclude here by default)
+
+# Docker
+.dockerignore
+
+# Playbook cache (runtime data)
+playbook_cache/