feat: enhance child edit and view components with improved form handling and validation

- Added `requireDirty` prop to `EntityEditForm` for dirty state management.
- Updated `ChildEditView` to handle initial data loading and image selection more robustly.
- Refactored `ChildView` to remove unused reward dialog logic and prevent API calls in child mode.
- Improved type definitions for form fields and initial data in `ChildEditView`.
- Enhanced error handling in form submissions across components.
- Implemented cross-tab logout synchronization on password reset in the auth store.
- Added tests for login and entity edit form functionalities to ensure proper behavior.
- Introduced global fetch interceptor for handling unauthorized responses.
- Documented password reset flow and its implications on session management.

frontend/vue-app/src/common/__tests__/backendEvents.spec.ts

@@ -0,0 +1,106 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
+import { mount } from '@vue/test-utils'
+import { defineComponent, h, toRef } from 'vue'
+import { useBackendEvents } from '../backendEvents'
+
+const { emitMock } = vi.hoisted(() => ({
+  emitMock: vi.fn(),
+}))
+
+vi.mock('../eventBus', () => ({
+  eventBus: {
+    emit: emitMock,
+  },
+}))
+
+class MockEventSource {
+  static instances: MockEventSource[] = []
+  public onmessage: ((event: MessageEvent) => void) | null = null
+  public close = vi.fn(() => {
+    this.closed = true
+  })
+  public closed = false
+
+  constructor(public url: string) {
+    MockEventSource.instances.push(this)
+  }
+}
+
+const TestHarness = defineComponent({
+  name: 'BackendEventsHarness',
+  props: {
+    userId: {
+      type: String,
+      required: true,
+    },
+  },
+  setup(props) {
+    useBackendEvents(toRef(props, 'userId'))
+    return () => h('div')
+  },
+})
+
+describe('useBackendEvents', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    MockEventSource.instances = []
+    vi.stubGlobal('EventSource', MockEventSource)
+  })
+
+  afterEach(() => {
+    vi.unstubAllGlobals()
+  })
+
+  it('connects when user id becomes available after mount', async () => {
+    const wrapper = mount(TestHarness, { props: { userId: '' } })
+
+    expect(MockEventSource.instances.length).toBe(0)
+
+    await wrapper.setProps({ userId: 'user-1' })
+
+    expect(MockEventSource.instances.length).toBe(1)
+    expect(MockEventSource.instances[0]?.url).toBe('/events?user_id=user-1')
+  })
+
+  it('reconnects when user id changes and closes previous connection', async () => {
+    const wrapper = mount(TestHarness, { props: { userId: 'user-1' } })
+
+    expect(MockEventSource.instances.length).toBe(1)
+    const firstConnection = MockEventSource.instances[0]
+
+    await wrapper.setProps({ userId: 'user-2' })
+
+    expect(firstConnection?.close).toHaveBeenCalledTimes(1)
+    expect(MockEventSource.instances.length).toBe(2)
+    expect(MockEventSource.instances[1]?.url).toBe('/events?user_id=user-2')
+  })
+
+  it('emits parsed backend events on message', async () => {
+    mount(TestHarness, { props: { userId: 'user-1' } })
+
+    const connection = MockEventSource.instances[0]
+    expect(connection).toBeDefined()
+
+    connection?.onmessage?.({
+      data: JSON.stringify({ type: 'profile_updated', payload: { id: 'user-1' } }),
+    } as MessageEvent)
+
+    expect(emitMock).toHaveBeenCalledWith('profile_updated', {
+      type: 'profile_updated',
+      payload: { id: 'user-1' },
+    })
+    expect(emitMock).toHaveBeenCalledWith('sse', {
+      type: 'profile_updated',
+      payload: { id: 'user-1' },
+    })
+  })
+
+  it('closes the event source on unmount', () => {
+    const wrapper = mount(TestHarness, { props: { userId: 'user-1' } })
+
+    const connection = MockEventSource.instances[0]
+    wrapper.unmount()
+
+    expect(connection?.close).toHaveBeenCalledTimes(1)
+  })
+})