feat(dashboard): add accessible dashboard status semantics

[s6pa1rta3n-lab]

Accessible Dashboard Status Semantics

Closes #1366

Summary

Enhances dashboard accessibility semantics across stream lifecycle states (active, paused, ended, failed, draft, cancelled, withdrawn):

• Semantic landmarks & status roles: Added role="status" and accessible labels across StatusBadge, StreamRow, StreamProgress, StickyStreamHeader, and StreamEndedCard.
• Failed status support: Added failed state handling with dedicated glyph, non-color pattern cues, ARIA live announcements, and actionable retry flows.
• Keyboard operability: Ensured all dashboard controls and action buttons are focusable, keyboard operable, and carry clear accessible labels.
• Focus restoration: Restored focus to triggering elements after action dispatches and async error states.
• Comprehensive test suite: Added DashboardStatusSemantics.test.tsx verifying all accessibility criteria across all lifecycle states.

Acceptance Criteria Checklist

• All controls are keyboard operable.
• Status is conveyed in text (never color alone).
• Focus is visible and restored.
• Tests cover active, paused, ended, and failed states.
• Pass local tests and linting.

Payout Routing

• EVM (Base/Arbitrum/Polygon/ETH): 0xF46C9F6d70C50BF81ef3588AB523a90a594a2F89
• Stellar: GCL6OXAMLD75BMTINA6EMRUDWK5THQUSHMYNLSNBCJAPZJHNYJTUNIBC