scenario-unity-performance

# Unity performance (performance engineer) Expert performance work is a measurement discipline: a budget in milliseconds, the bounding thread named before any change, the biggest measured cost fixed first, structure before tuning, and every fix proven with before/after numbers from a development player. An agent does all of it headless: `AgentProfile` in Editor Play mode to iterate, `PerfProbe` in a batch-mode player for verdicts, `PerfCapture` to attribute costs from a Profiler capture, `metal_trace` for GPU time, `PerfBuild` for size. Target: Unity 6000.3.21f1, URP 17.3, macOS Apple Silicon. If a sibling skill named here is missing from your available skills, ask the user to install it (`npx skills add scenario-labs/skills --skill <name>`); unattended, proceed from tool schemas and flag the gap. **REQUIRED BACKGROUND:** scenario-unity-expert (channels, review loop, 6.3 traps, `ut_*` toolkit). ## Stance (the expert delta) 1. **Name the bound before touching anything.** "If you speed up the GPU when your profile looks like this it's not going to run any faster" (Peter Hall, Unity Profiler team, _cV1B2hqXGI [00:05:50]). Observed: removing 1.36 MB of garbage per frame did not move a frame bound by 5,946 SetPass calls. GPU bound needs GPU timing; the Frame Debugger has none (Hall [frame 00:09:18]). 2. **Players decide, the Editor iterates.** The authority is a development build on the lowest target device (profiling e-book p. 18). GRD: 4.4x in a 2M-instance stress test, 2.07...