Make Zulip Integrations Accessible, Bot Permissions Management and OAuth System

This proposal aims to improve Zulip integrations by making them more accessible and user-friendly. It introduces a backend permissions system to enforce bot access levels at runtime, the project replaces API key-based authentication with an OAuth 2.0 flow using django-oauth-toolkit. Additionally, it redesigns the integrations UI to use a “Add to Zulip” button which eliminates the manual bot setup. Together, these changes simplify integration workflows for non-technical users while making the integrations more secure.