feat: migrate hardcoded colors to --rs-* CSS variables across 18 modules
Replace structural UI colors with theme-aware CSS custom properties so
all rApp modules respond correctly to light/dark theme switching.
Covers: folk-social-post, folk-forum-dashboard, folk-video-player,
folk-video-chat, folk-thread-gallery, folk-campaign-manager,
folk-wallet-viewer, folk-vote-dashboard, folk-swag-designer,
folk-cart-shop, folk-workflow-block, folk-choices-dashboard,
folk-pubs-editor, folk-book-shelf, folk-flows-app, folk-analytics-view,
folk-campaign-planner, and flows.css canvas background.
Intentionally preserved: platform brand colors, chain colors,
data-viz/chart colors, video player black, call action buttons.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Jeff Emmett
72100c0922