Implement profile management (task 14)

- Add updateProfile and updatePassword server actions
- Add getUserProfile function with sensitive data protection
- Create ProfileForm component for name and email updates
- Create PasswordChangeForm component with current password verification
- Create profile page at /profile with all profile management features
- Add profile and invitations navigation links to main page
- Implement email uniqueness validation
- Implement password hashing on password change

Requirements: 7.1, 7.2, 7.3, 7.4, 7.5

.kiro/specs/user-auth-and-sharing/tasks.md

@@ -200,7 +200,7 @@
   - **Property 24: Permission update enforcement**
   - **Validates: Requirements 6.5**
 
-- [ ] 13. Create sharing UI components
+- [x] 13. Create sharing UI components
   - Build InvitationCard component
   - Build CollaboratorList component
   - Build ShareListModal component
@@ -208,7 +208,7 @@
   - Add invitations page
   - _Requirements: 5.1, 5.4, 8.1, 8.2_
 
-- [ ] 14. Implement profile management
+- [-] 14. Implement profile management
   - Create profile page and ProfileForm component
   - Implement updateProfile server action
   - Create PasswordChangeForm component