[Platform] [User Notifications][TUS] Events are created when Comments are added to Idea

[becevka]

Summary
In order to support User Notifications, we need to create events upon Idea comments.

Describe the solution you'd like
Event Collection should consist of the following fields:

• entityId, numeric id of the business-level entity (IdeaCard)
• entityType, enum value of business-level entity type (IdeaCard only for now)
• title, top-level description of event
• content, details of the event
• createdDateTime, date when event was created

When user creates a comment to an existing Idea, event is generated with the Title "{userName} commented on {ideaName}" and content will be comment itself.

Note: entityId and entityType will still point to IdeaCard entity
Events endpoints should not be available through API.

Acceptance Criteria

Generated by Zenhub AI

• Scenario: Create event when comment is added to an idea
  • Given a comment is added to an idea
  • When an event is created for the comment
  • Then the event should have the following fields:
    • entityId: the IdeaCard id
    • entityType: IdeaCard
    • title: "{userName} commented on {ideaName}"
    • content: the comment text
    • createdDateTime: the date when the event was created