chore: remove unused imports in Avatar component

[Copilot]

Removed unused useEffect and User type imports from Avatar.tsx that were flagged in code review.

Changes:

• Removed useEffect from React imports (not used after refactoring toggle logic)
• Removed User type import (component uses useUser hook with type inference)

// Before
import React, { FC, useState, useEffect } from 'react';
import type { User } from '../../../../types/models';

// After
import React, { FC, useState } from 'react';

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