feat(dashboard): rebuild collections page

[jal-co]

What

• rebuild /dashboard/collections as a full-width responsive management surface
• add collection, component-entry, live-entry, and for-sale summary metrics
• add collection/component search and sale-status filtering
• present collections as visual cards with member readiness, install command, price state, and public-page access
• add confirmed destructive deletion with visible failure feedback
• improve create/edit component selection semantics with a fieldset and labeled checkboxes
• keep collection selling, editing, eligibility, pricing, and external-sale behavior intact
• include the requested subheading example: “For example, an entire shadcn registry may be compiled into a collection.”

Why

The previous Collections page was constrained to a narrow column and reduced each collection to a utility row. The new layout uses the full dashboard canvas and makes member readiness, sale state, install identity, and available actions scannable as collection counts grow.

How

• follows Interface Craft principles with a strong visual entry point, progressive disclosure, consistent card anatomy, and state-specific feedback
• uses existing shadcn/Radix inputs, selects, dialogs, tooltips, buttons, and empty states
• keeps hover feedback to subtle color, border, and shadow changes without positional movement
• uses amber only for money/external sale state and emerald only for scoped live-member evidence
• disables public-page navigation when a collection has no live members
• keeps all existing server functions and authorization rules unchanged

Testing

• web TypeScript check
• 77 unit tests
• production build
• Storybook build
• desktop browser check at 1440 × 900
• tablet filter interaction check at 768 × 1024
• mobile browser check at 390 × 844
• create/edit fieldset and 10 component checkboxes verified
• sale-management dialog verified
• delete-confirmation dialog verified
• search and sale-filter empty states verified
• accessible names checked for every main-content button
• no horizontal overflow
• exact required subheading copy verified in rendered DOM
• git diff --check

Screenshots

• Before: /tmp/collections-before-desktop.png
• After desktop: /tmp/collections-final-1440.png
• After mobile: /tmp/collections-final-390.png