Added documentation for the new Limits page feature that allows users to
view their current limits, quotas, and rate limit usage in real-time
from the dashboard. The page displays rate limit token availability,
quota usage, and plan features for organizations.

## Files changed
- `docs/limits.mdx` - Added introductory paragraph about the new Limits
page in the dashboard

Generated from [feat(webapp): New limits
page](https://github.com/triggerdotdev/trigger.dev/pull/2885) @samejr

Co-authored-by: mintlify[bot] <109931778+mintlify[bot]@users.noreply.github.com>
Co-authored-by: James Ritchie <james@trigger.dev>