PRXT - fix: improve DateAccordion accessibility

[punk6529]

Summary

• replace the DateAccordion header div with a semantic button that spans the full width and carries aria attributes
• generate a stable id via useId to wire the button aria-controls to the animated panel
• update the DateAccordion unit tests to cover the new button behavior and aria metadata

Testing

• npx jest --runTestsByPath tests/components/common/DateAccordion.test.tsx --watchAll=false --coverage=false --silent
• npm run lint
• npm run type-check (fails: existing TypeScript errors across unrelated test files)

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https://chatgpt.com/codex/tasks/task_e_68c93fc96ce08321849fc9d5d955c63d

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[prxt6529]

Will be done in #1516