Add notifications web module (#28983)

* Add notifications web module

* implement getThreadMessage in chat

* Save comment mention notification

* check if recipient is a real user

* move commentMentionDelay

* use module-hooks types

* remove router

* updated collection name

GitOrigin-RevId: cf8240c88aac7d7e4de4bf51cfe2608b6b7e7918

services/web/types/module-hooks.ts

@@ -0,0 +1,10 @@
+/**
+ * Types for module hook events fired across the application
+ */
+
+export type CommentAddedEvent = {
+  projectId: string
+  userId: string
+  threadId: string
+  messageId: string
+}