End-to-end planning, building, and testing of small-scale browser games in SvelteKit + TypeScript running in Docker, including scaffolding, game loop, input, UI, tests, and Docker dev/release setups. Use when a user asks to create or modify a SvelteKit game project, prototype a simple single-player game, or add tests. When requirements are unclear, ask clarifying questions and offer to choose defaults automatically if the user prefers. This skill uses SvelteKit+TS in Docker only (debug hot-reload + nginx release); do not switch stacks unless the user explicitly asks to change scope. Not for multiplayer, servers, or backend services.