Feat: #2748 (Backend) IdeaSpace Comment Notifications

[tanmaydhal]

NOTE

Mark Notifications as Read should be implemented alongside this feature. Otherwise these toasts will get noisy very quickly

Background

This PR is 1 of 2 PR's. This implements backend changes for #2748. This should be merged BEFORE the Frontend PR.

Summary

Implements the backend notification logic for comment activity on ideas. When a user comments on an idea, the relevant users are notified via the existing event/notification/subscription model.

Changes

comment/content-types/comment/lifecycles.js

• Added afterCreate lifecycle hook to handle notification creation when a comment is posted
• Fetches the idea owner and existing subscribers for the idea
• Builds a set of users to notify, explicitly excluding the commenter (no self-notifications)
• Creates a subscription for the commenter if one doesn't already exist
• Creates a single event record and one notification per user to notify

event/content-types/event/lifecycles.js

• Added a guard to skip automatic notification creation for comment events (action === "Commented" or entityType === "Comment")
• This prevents duplicate notifications since comment notifications are handled entirely in comment/lifecycles.js

Testing

• Tested locally using two accounts: one as idea owner, one as commenter. Verified in Strapi admin that exactly 1 notification is created for the correct user with no duplicates or self-notifications.