[Feature] Add reusable permission-handling foundation

[ducbm051291]

Why

Teams repeatedly rebuild permission status handling and request flows. The template should provide a reusable base so projects can start from a shared pattern.

Acceptance Criteria

• A shared permission status model exists.
• The template defines a reusable interface for checking and requesting permissions.
• Notification permission is supported as the first concrete example.
• The design can be extended later for location, camera, or photo library permissions.

Design

N/A

Resources

• Apple UserNotifications documentation
• Notification permission flow reference from cbtl-nexus-ios