Integrating v2 docs to repo

[DeveloperAlly]

NOTE: DO NOT MERGE THIS PR

This is a draft only - to provide a public link for reviewing documentation changes before a final publishable version is ready.

PR Summary

This pull request introduces updates to documentation and configuration files in preparation for a new version of the docs, along with minor style and command changes. The main changes include the addition of a V2 migration plan, renaming and formatting improvements to the main config file, and a small CSS tweak for navigation highlighting.

Documentation migration and planning:

• Added a new README_V2.md file outlining the V2 documentation migration plan, including a TODO list for global settings and features to be implemented.

Configuration file updates and formatting:

• Renamed mint.json to mintOld.json and upgraded to use docs.json [current Mintlify process]

Command update for local development:

• Updated the documentation in README.md to use the mint dev command instead of mintlify dev for running the local documentation server.

Styling changes:

• Added a CSS rule in style.css to highlight specific navigation tab links for V2 testing purposes.