ADDED Requirements

Requirement: Assignment notification email

The system SHALL send an email to a task's new assignee within 60 seconds of the task being assigned to them.

Scenario: Task assigned to another member

• WHEN Alice assigns a task to Bob
• THEN Bob receives an email within 60 seconds containing the task title and a link to the task

Scenario: Self-assignment

• WHEN a member assigns a task to themselves
• THEN no notification email is sent

Requirement: Notification preferences

Users SHALL be able to opt out of notification emails for each project they belong to, and the system MUST honor the opt-out for all subsequent notifications.

Scenario: Opted-out user is assigned a task

• WHEN Bob has opted out of emails for project "Website" and is assigned a task in "Website"
• THEN no email is sent to Bob

Scenario: Opt-out is per project

• WHEN Bob has opted out for project "Website" but not for project "Mobile"
• THEN Bob still receives assignment emails for tasks in "Mobile"