[ACC-006] Accounts: User profile page (name, email, preferences)

## Overview
Build the user profile page where users can view and update their personal info, manage notification preferences, and access account sub-sections.

## Acceptance Criteria
- [ ] Route: `/account` (redirect to login if not authenticated)
- [ ] Sections: Profile Info, Security, Notifications, Wishlist (#9), Order History (#17)
- [ ] Edit first name, last name, display name, phone number
- [ ] Change email (requires re-verification via #6)
- [ ] Change password (requires current password)
- [ ] Notification preferences: order updates, promotions, newsletters
- [ ] Delete account option (soft delete, 30-day recovery window)

## Depends On
- #5 AUTH-001 — page is gated behind authentication
- #6 AUTH-002 — registration data populates initial profile

## Blocks
- #17 ACC-012 (order history is a sub-section of this page)
- #22 SUP-002 (contact form pre-fills from profile data)