feat(issues): rewrite issues page with component decomposition and persisted filters
- Decompose monolithic 472-line page.tsx into focused components:
board-card, board-column, board-view, list-row, list-view,
issues-header, issues-page
- Add view-store with Zustand persist for viewMode and multi-select
status/priority filters
- Fix kanban DnD with pointerWithin + closestCenter collision detection
- Add workspace breadcrumb header and Linear-style filter dropdowns
using DropdownMenu with CheckboxItem for multi-select
- Status filter hides kanban columns, priority filter hides cards
- Drop target highlight with bg-accent
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
586a4916d1