Improve Documentation Structure and Accessibility in Markdown Files (#69)

* Major refactor

- Move configure and tools to top level
- Update category positions
- Move images to static dir
- Update links

* Update image file name in introduction.md

* Update sidebar positions for integrations documentation

* Update category positions for documentation

* Update knowledge base integration description

* Update FAQ with CodeRabbit comparison and CodeRabbit's uniqueness

* Update redirects in docusaurus.config.ts

* Update Jira and Linear integration configuration in knowledge base

* Update GitLab integration documentation

Author: hasit