Expand shared component library beyond initial 4 components

[chubes4]

Context

@extrachill/components@1.0.0 ships with 4 React admin components. As more plugins migrate to the shared package ecosystem, common UI patterns should be extracted here.

Candidates for extraction

• Search/filter bars (used in admin-tools, community, analytics)
• Data tables with pagination (used across most admin panels)
• Status badges / pill components
• Modal/dialog wrappers
• Chart wrapper components (artist-platform uses chart.js)
• Loading/skeleton states

Principles

• Only extract when 2+ plugins share the same pattern
• Components must use --datamachine-* design tokens (theme-agnostic)
• Each component should be tree-shakeable

Current components

Review what shipped in v1.0.0 and identify the next highest-value extractions.