This PR fixes several issues with the 'Add Groups'/'Add Owner Groups' buttons on role list pages

• Buttons are now displayed to admins on externally managed role pages
• Buttons will only appear to non-admins if they own a role and also own groups that do no have tag constraints that would prevent them from adding the role to the group
• Removed disallowedGroups since it did not work and was dead code
• Fixed dialog group filter (constraint and ownership aware)
• Make the group selection dropdown in the dialog prepopulate available groups
• Corrected dialog informational message and added part about tag constraints

No visual changes besides updating informational message

Also fixed an issue with the app not loading in local dev