This PR has the following changes - Add `LINEAR_CLIENT_ID` and `LINEAR_CLIENT_SECRET` to installation config - Add Linear config to super_admin/features.yml - Replace usage of ENV.fetch with GlobalConfigService.load for fetch Client Id and Secret.
Fixes https://linear.app/chatwoot/issue/CW-3417/oauth-20-authentication We are planning to publish the Chatwoot app in the Linear [integration list](https://linear.app/docs/integration-directory). While we currently use token-based authentication, Linear recommends OAuth2 authentication. This PR implements OAuth2 support. --------- Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com> Co-authored-by: Shivam Mishra <scm.mymail@gmail.com>