hyperbuild-chooselisted

# /hyperbuild-choose — record the design choice, release Stage B You are executing the human checkpoint of the hyperbuild pipeline. Step 12 (design gate) stopped the run and asked the user to pick one of three designs; the user has now answered. Your only job: validate, record, copy, flip the manifest, and hand control back to the router. **THIS SKILL DOES NO BUILD WORK.** Step 13 scaffolds; step 14 implements. If you find yourself about to create project files, run a scaffolder, or write code, STOP — record the decision and invoke the router. ## Arguments - **arg 1 (required):** the design choice — `a`, `b`, or `c`. Case-insensitive; normalize to lowercase. - **arg 2 (optional):** a platform override (e.g. `flutter`, `swiftui`, `react-native`, `nextjs`). Only honor it if it differs from the manifest's `platform`. If arg 1 is missing or is not `a`/`b`/`c`: read the title of each `runs/<run_tag>/designs/{a,b,c}/design-system.md`, show the user the three letters with their design names, and stop. Record nothing. (Exception: if the argument uniquely matches one design's NAME, accept it, note the mapping in the decision file, and proceed with the corresponding letter.) ## Inputs - `runs/*/manifest.json` — run_tag, stage, platform, steps, design_choice, blocked_on - `runs/<run_tag>/designs/<choice>/design-system.md` — the chosen system (its title is the design name) - `runs/<run_tag>/designs/<choice>/tokens.css` — the chosen tokens - `runs/<run_tag>/designs/<choice>/mo