- Add internal/crm client with CanonicalJSON and HMAC-SHA256 signing for POST /api/public/leads
- Add database migration 0026_crm_deals.sql with crm_deal_id and partial indexes
- Add async lead intake dispatch to new CRM in handlers_leads.go
- Support dual-mode booking confirmation (CRM_MODE=both/crm_only/bitrix_only) in booking_confirm.go
- Add LinkCRM endpoint to bridge_1c.py and onec.Client
- Update config and env examples with CRM_API_URL, CRM_LEAD_INTAKE_SECRET, CRM_MODE
