feat: extend advanced schema for API

[botprzemek]

Description

Extend multi-tenant friendly SQLite schema for API - Marketing tools.

File: seed.sql

Suggested approach

• Add additional fields to Organization (Refactored Tenant) and Company tables,
• New tables:

1. Users,
2. RBAC (User memberships, Roles, Permissions),
3. Lists (of Companies),
4. Tags (for Lists),
5. Mail templates,
6. Mail queues,
7. Campaigns,
8. Campaigns steps,
9. Organization settings,
10. User settings,

Related issues

Depends on #9