Add the ability to limit permission for each mcp tool

Problem/Motivation

In the current state, mcp auth allows access to all tools exposed over mcp.
There are some tools (eg. all field api level tools) which should only be accessible to a use with 'content editor' role.
Whereas there are other tools (rag search) which should be accessible to 'anonymous' user or a use with 'search api consumer' role.

Steps to reproduce

1. Connect to mcp server
2. See all tools available over mcp

Proposed resolution

Add ability to control permission for each mcp plugin.

Remaining tasks

User interface changes

API changes

Data model changes