Uiux/payout ics export

[OLAMIGHTY010]

Resolves Issue #445

Description

This PR implements the ICS calendar export UX for the Payout Schedule page, enabling investors and issuers to easily subscribe to upcoming payouts across various calendar clients.

Key Changes

• Client Instruction Tabs: Replaced the static bulleted list with an interactive, tabbed interface to display client-specific setup instructions (Google, Outlook, Apple Calendar).
• Revoke Confirmation Flow: Added a safety confirmation step (Are you sure? Existing calendar syncs will break.) when revoking a subscription URL to prevent accidental breakages.
• Last Used & Regenerate: The regenerate button now instantly cycles the URL token and resets the "Last Used" timestamp to ensure synchronization integrity.
• Edge Cases & Accessibility:
  • Implemented explicit dir="ltr" for the URL input and updated styles for RTL layout compatibility to prevent garbled text.
  • Added truncation styles (text-overflow: ellipsis) for very long subscription URLs to prevent layout breakage.
  • Verified ARIA roles (tablist, tab, tabpanel) and button labels for screen reader accessibility (WCAG 2.1 AA).
• Test Coverage: Expanded CalendarExportDialog.test.tsx to include new test cases for tab switching, the multi-step revoke flow, and revocation cancelation.

How to Test

1. Navigate to the Payout Schedule page and click Subscribe.
2. Verify you can tab through Google, Outlook, and Apple instructions seamlessly.
3. Click the Copy button and verify the fallback behaves correctly.
4. Click Revoke, and ensure the confirmation prompt appears before the URL is actually nullified.
5. Review the component under an RTL language layout.