rails-wasm-author-constraints

Use this skill whenever checking if a Rails feature or gem works in WASM, or understanding what's real vs. conceptual in lessons. Trigger on: 'does X work in WASM', 'can I use this gem', 'gem compatibility', 'WASM limitation', 'what works', 'supported features', 'PGLite', 'threading', 'Net::HTTP', 'ActionCable', 'background jobs', 'can I teach X', 'bundle install in WASM', 'conceptual vs real', or any Rails capability question — even without mentioning WASM. Authoritative compatibility matrix: which features work, which are shimmed, which are impossible, plus gem tiers, PGLite behavior, boot timing, and conceptual-vs-real operations. General Rails knowledge is insufficient here. Do NOT use for file organization (use rails-file-management) or frontmatter (use tutorial-lesson-config).