Apply or review multi-version support compliance for first-party Nx plugins. Primary entry point: a Linear task ID (NXC-XXXX) from the "Multi-version supported across plugins" milestone — the task carries the resolved support window, findings, and "Needs human decision" items. Falls back to self-discovery when no task exists. Use when asked to "fix multi-version compliance for @nx/X", "do NXC-XXXX", "review this compliance PR", or when working on a branch / PR titled "multi-version support compliance for @nx/X". Covers the canonical shape (assertSupportedPackageVersion, all-generators-enforce-floor.spec.ts, peer dep alignment, requires-gate auditing, user-pin preservation, executor / inferred-plugin feature gating).