Add the ToastUI editor dependency

What does this MR do?

This MR adds the ToastUI Editor to the codebase and wraps it in a Vue component.

Changes in this MR are part of delivering the feature described in #214559 (closed).

Screenshots

Changes in this MR has no visual impact.

TODO

• Add @toast-ui/vue-editor dependency.
• Add the necessary test coverage.
• Wrap ToastUI editor in a Vue component (outside of the SSE directory).

Does this MR meet the acceptance criteria?

Conformity

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.

Issue #215117 (closed)