Add comprehensive test coverage for platform marketing homepage API: - test_pricing.py: 17 tests for tiers, add-ons, pricing endpoints - test_letzshop_vendors.py: 22 tests for vendor lookup and claiming - test_signup.py: 28 tests for multi-step signup flow Fix signup.py to use correct password hashing from middleware/auth.py and properly create Company with owner_user_id. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>