86cygkra3-add-multi-role-support-and-role-based-security-in-splitora RBAC added

[Satwik-Bhardwaj]

1. Added role in JWT token.
2. Increased the access token time and refresh token by 10 times.
3. Added authorisation for many endpoints (but not added for all). Admins have access to write and read some of that endpoint, while a regular user can't access entities belonging to another user.
4. Added a unique constraint for phone number and country code.
5. Added access denied exception to return forbidden code.