fix(frontend): a11y for user facing pages

[surt91]

This PR achieves a Lighthouse rating of 100 on the main chat page.

And introduces automatic checks for accessibility in the e2e tests.

Related to #203 and #258

[Copilot]

Pull Request Overview

This PR improves accessibility across user-facing pages to achieve a Lighthouse score of 100, and introduces automated accessibility testing in the e2e test suite. The changes focus on adding proper semantic HTML, ARIA labels, and screen reader support.

Key changes:

• Added semantic HTML elements (header, main, nav, aside) to replace generic divs
• Added ARIA labels to interactive elements lacking accessible names (buttons, inputs, textareas)
• Introduced automated a11y testing using @axe-core/playwright in e2e tests

Reviewed Changes

Copilot reviewed 27 out of 28 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
frontend/src/texts/languages/en.ts	Added accessibility-focused text keys for ARIA labels
frontend/src/texts/languages/de.ts	Added German translations for accessibility text keys
frontend/src/texts/index.ts	Exposed new accessibility text functions
frontend/src/pages/login/LoginPage.tsx	Replaced divs with semantic HTML (main, header, section, nav) and changed h2 to h1
frontend/src/pages/chat/files/Files.tsx	Added aria-label to file input and changed button colors from "gray" to "#666"
frontend/src/pages/chat/files/FileCard.tsx	Added aria-label to file selection checkbox
frontend/src/pages/chat/conversation/FileItem.tsx	Added aria-label to file delete button
frontend/src/pages/chat/conversation/ConversationPage.tsx	Added aria-label to scroll-to-bottom button
frontend/src/pages/chat/conversation/ChatItem/HumanChatItem.tsx	Added aria-labels to edit textarea and action buttons
frontend/src/pages/chat/conversation/ChatItem/AIChatItemActions.tsx	Added aria-labels to copy and rate action buttons
frontend/src/pages/chat/conversation/ChatInput.tsx	Added aria-labels to chat input and send button, replaced Icon component with IconArrowUp
frontend/src/pages/chat/ConversationItems.tsx	Changed h4 to h2 for date group headings
frontend/src/pages/chat/ConversationItem.tsx	Restructured conversation item layout and added aria-labels to menu button
frontend/src/pages/chat/ChatPage.tsx	Added semantic HTML (header, nav, main, aside) with aria-labels
frontend/src/pages/admin/theme/LogoUpload.tsx	Added aria-label to logo upload input
frontend/src/components/UserProfileModal.tsx	Added data-testid for test reliability
frontend/src/components/PdfControlBar.tsx	Added aria-label to page number input
frontend/src/components/NavigationBar.ui-unit.spec.tsx	Updated tests to verify sr-only h1 element
frontend/src/components/NavigationBar.tsx	Added sr-only h1 for screen readers
frontend/src/components/Forms.tsx	Added aria-labels to file type and size limit inputs
frontend/src/components/CollapseButton.tsx	Added aria-label using tooltip text
e2e/tests/utils/helper.ts	Added expectA11yCompliant helper function
e2e/tests/administration/userSettings.spec.ts	Updated selector for modal close button
e2e/package.json	Added @axe-core/playwright dependency
e2e/extension-tests/azure-user-args.spec.ts	Added accessibility check
e2e/extension-tests/azure-open-ai.spec.ts	Added accessibility checks at multiple test points
e2e/extension-tests/a11y.spec.ts	New dedicated accessibility test file

Files not reviewed (1)

• e2e/package-lock.json: Language not supported

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[Copilot]

Pull Request Overview

Copilot reviewed 27 out of 28 changed files in this pull request and generated 2 comments.

Files not reviewed (1)

• e2e/package-lock.json: Language not supported

---

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