TypeScript and lint rules

Every .ts/.tsx file of the app compiles under one strict tsconfig set and passes one ESLint config with no warnings, no inline disables and hard size limits; Prettier formats and knip finds dead code. Style is enforced by machines or it does not exist. This skill holds those configs, the limits table, the forbidden patterns, the TSDoc contract, and two checkers that prove the repo still follows them.

Rules that must hold