docs: create roadmap (5 phases) and research
Phases:
1. Foundation: tenant isolation, auth, Docker, RBAC
2. Subscriber & Billing Core: subscribers, invoicing, payments, accounting ledger
3. Operational Modules: collectors, ticketing, job orders, technicians
4. Inventory, Expenses & Reports: event-ledger inventory, expenses, financial statements
5. Visibility & Client Portal: dashboard, client self-service, integration & e2e tests
All 66 v1 requirements mapped to phases.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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