Initial project structure

Scaffold all modules, route stubs, data models, and config.
No logic implemented yet — all core methods raise NotImplementedError.
Establishes the full directory layout matching the architecture in CLAUDE.md.

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

.gitignore

@@ -0,0 +1,29 @@
+# Environment
+.env
+
+# Python
+__pycache__/
+*.pyc
+*.pyo
+*.pyd
+.Python
+*.egg-info/
+dist/
+build/
+
+# Virtual environments
+.venv/
+venv/
+env/
+
+# Testing
+.pytest_cache/
+.coverage
+htmlcov/
+
+# Logs
+logs/
+
+# IDE
+.vscode/
+.idea/