[sofyakurilova]

Update components, templates, and styles across modules/ui to satisfy GAR 2027 accessibility requirements:

• Accessibility Labels & Relationships (P0):
  • Fix broken aria-labelledby reference and associate description text via aria-describedby in settings-dropdown.
  • Fix uninterpolated aria-label expression on delete-report button.
  • Add role="button" and contextual aria-label host bindings to app-download-report-zip.
  • Associate multi-select checkbox groups and test module groups with their headings/descriptions using role="group", aria-labelledby, and aria-describedby in dynamic-form, device-qualification-from, and device-tests; remove overriding aria-label on required field errors.
  • Fix copy-pasted mat-sort-header sortActionDescription values and add accessible labels to icon-only table header columns in certificates-table and testrun-table.
  • Add aria-label attributes to start/end date range inputs in filter-dialog.
  • Add semantic list roles (role="list", role="listitem"), region labels, and contextual action menu labels ("Actions for ") in list-layout and list-item.
• Screen Reader Updates, Focus & Keyboard Navigation (P0):
  • Change testrun-status-card live region from assertive alert to polite status and deduplicate countdown timer live announcements.
  • Add visible :focus-within outline and >= 3:1 border contrast to the custom report search input.
  • Add Escape key dismissal and aria-haspopup/aria-expanded attributes to download-options and help-tip popups, and Space key activation to role="button" links in consent-dialog.
• Clear Purpose, Instructions, Text Alternatives & Headings (P1):
  • Replace vague "here" link text with descriptive "Google Terms of Service" and underline inline links so they do not rely on color alone.
  • Add persistent mat-hint format instructions for device form fields and date range inputs.
  • Hide decorative icons/illustrations from assistive tech (alt="", aria-hidden="true") in empty-message, side-button-menu, and profile-item.
  • Add role="heading" aria-level="2" to modal dialog titles.
• Target Size, Contrast, Text Spacing & Responsive Reflow (P2):
  • Expand stepper indicator hit area to >= 24x24px, increase inactive border contrast, and expose aria-current="step".
  • Add tooltips for truncated report metadata values and replace fixed heights and hidden overflow with min-height and responsive reflow rules.