[Volunteer Flow] Exit Attendance: Implement "Thank You"

Issue Summary

Overview

Implement a streamlined exit flow for volunteers in the medical camp system. This includes a dedicated "Thank You" screen and removal of obsolete certificate-related functionality to improve UI clarity and volunteer experience.

Problem Statement

Current Behavior: When a volunteer's exit attendance is marked by an admin, the volunteer's app stays on the QR generation screen or shows confusing "Download Certificate" options that are no longer functional.
Affected Users: All volunteers participating in medical camps.
Impact: Volunteers are unsure if their exit has been successfully recorded and the interface remains cluttered with unused actions.
Reproduction: Attend a camp as a volunteer, have an admin mark your exit attendance, and observe that the volunteer interface does not transition to a completion state.

Proposed Solution

Approach: Introduce a new is_exited state in the volunteer camp status. When this state is active, the frontend will replace the QR scanner and attendance dashboard with a minimalist "Thank You" screen.
Components to Change:
- VolunteerCampFlow.tsx: Handle conditional rendering of the exit screen.
- QRGenerationPage.tsx: Update the status refresh logic.
Dependencies: Requires the backend to return is_exited in the signup-status API.

Test-Driven Development

Acceptance Criteria (Given-When-Then)

Scenario 1: Volunteer has completed attendance (Exited)

Given a volunteer is logged into the medical camp flow
  And the backend returns `is_exited: true`
 When the volunteer views the dashboard
 Then the "Thank You for Your Service" screen should be displayed
  And the QR generation button should be hidden
  And the "Download Certificate" button should be hidden

Scenario 2: Volunteer refreshes status after exit record

Given a volunteer is on the QR generation screen
 When the volunteer clicks "Refresh Status" and the backend returns `is_exited: true`
 Then a success notification should appear
  And the UI should transition to the "Thank You" screen

Test Cases

Test ID	Test Description	Precondition	Test Steps	Expected Result	Priority
TC-001	Verify "Thank You" screen rendering	`is_exited` is true	1. Load dashboard 2. Check UI elements	Appreciation message shown	High
TC-002	Manual status check during exit	`is_exited` transitions to true	1. Click Refresh 2. Check toast	Success toast + Redirect	High
TC-003	Certificate button removal	Any state	1. View dashboard	No certificate button exists	Medium

Unit Test Requirements

Components/Functions to Test:

Module/Component	Function/Hook	Test Cases to Cover
`VolunteerCampFlow.tsx`	Component Rendering	TC-001
`QRGenerationPage.tsx`	`handleCheckStatus`	TC-002

Test Assertions Required:

Renders correctly with initial state
Handles user interaction (Refresh)
Updates UI state appropriately (Exited)
Handles success response

Implementation Details

Files to Change

File Path	Action	Purpose
`src/pages/volunteer/VolunteerCampFlow.tsx`	Modify	Implement exit screen rendering logic
`src/pages/volunteer/QRGenerationPage.tsx`	Modify	Update status check to handle exit state
`src/types/api.ts`	Modify	Add `is_exited` to API types
`src/locales/en/translations.json`	Modify	Add "Thank You" messaging
`tests/volunteers/VolunteerCampFlow.test.tsx`	Modify	Add coverage for the exit UI
`tests/App.test.tsx`	Modify	Increase timeout for complex component tests

Technical Considerations

State Sync: The is_exited flag is the single source of truth for the exit flow.
Bundling: Removing CertificatePage reduces redundant imports in the main bundle.

UI/UX Requirements

Layout: Centered appreciative message with a heart icon.
Animations: Subtle feedback when attendance is successfully verified via refresh.
Accessibility: Ensure the "Thank You" message is readable for screen readers.

Testing Strategy

Manual Testing

Test Environment:

Browser: Chrome
User Role: Volunteer

Manual Test Steps:

Navigate to the Volunteer Attendance dashboard.
Simulate/Verify exit attendance is marked.
Observe the transition to the "Thank You" screen.

Automated Testing

Unit Tests:

Component render tests (VolunteerCampFlow)
User interaction tests (QRGenerationPage refresh)
API integration tests (is_exited flag)

Definition of Done

Acceptance criteria met
All test cases executed and passing
Unit tests written and passing
Manual testing completed
No console errors or warnings
TypeScript types defined
ESLint/Prettier checks pass
i18n strings externalized