feat: display quick chat actions

Description

Adds quick chat actions (e.g. /tests) to the quick chat.

Related Issues

Resolves #1568 (closed)

How has this been tested?

Apart from the tests added in the MR, I've tested it locally.

Screenshots (if appropriate)

What CHANGELOG entry will this MR create?

• fix: Bug fix fixes - a user-facing issue in production - included in changelog
• feature: New feature - a user-facing change which adds functionality - included in changelog
• BREAKING CHANGE: (fix or feature that would cause existing functionality to change) - should bump major version, mentioned in the changelog
• None - other non-user-facing changes

Closes #1568 (closed)