V3 TypeScript compiler capability pack. By-value connector composition (service_kind=cli, no separate ingredient): one local tsc CLI ingredient exposes bounded project operations for readiness and TypeScript type-check diagnostics. Type-checking runs from an explicit project directory cwd supplied at execution time, uses one tsconfig path, disables emit, disables incremental state writes, disables pretty/ANSI output, avoids caller-supplied compiler flags, avoids shell wrappers, and keeps type errors visible as text output. The pack exposes no watch mode, build mode, JavaScript/declaration emit, plugin installation, package manager invocation, stdin, environment override, or arbitrary command execution. Requires tsc on PATH. Local and no-egress.