fix(patient): Remove unused and duplicate imports across patient app

[Muneerali199]

Summary

Running flutter analyze on the patient/ app reveals 10 unused import warnings and 2 duplicate import warnings across 8 files. These are warning-level diagnostics that clutter the codebase and can mask real dependency issues.

Affected Files

File	Issue
lib/core/repository/auth/auth_repository.dart	unused_import: package:flutter/material.dart
lib/presentation/assessments/assessment_screen.dart	unused_import: package:patient/presentation/result/result.dart
lib/presentation/auth/consultation_request_screen.dart	unused_import: package:patient/core/repository/auth/auth.dart, slot_booking_card.dart
lib/presentation/auth/consultation_slot_booking_screen.dart	unused_import: auth_provider.dart, provider.dart
lib/presentation/auth/personal_details_screen.dart	unused_import: assessment_screen.dart, home_screen.dart; duplicate_import
lib/presentation/result/result.dart	unused_import: dart:convert, flutter_dotenv, http
lib/provider/reports_provider.dart	unused_import: ../gen/assets.gen.dart
lib/provider/therapist_provider.dart	unused_import: flutter_dotenv, assessment_card_model.dart, supabase_assessments_repository.dart; duplicate_import

Steps to Reproduce

cd patient
flutter analyze

Expected Behavior

flutter analyze reports no unused_import or duplicate_import warnings.

Fix

Remove each flagged import. Where a duplicate_import exists, remove the duplicate line.