[transfix]

Minor release that publishes the libcvc family on cvcpkg, pycvc included. Joe gave the OK on 2026-10-17.

It carries:

• the world clock: lockstep and batch, followers, the sim.* binding, nav on the clock (world_clock: one clock for every simulation (lockstep/batch, followers, state-tree binding, sim_thread on the clock) #629, world clock C2: every libcvc demo on app.world_clock() (tick_scene binding, nav/lsystem/terrain demos) #630, tests(state): robust margins and deterministic ordering for the wait/future tests #631) and the thread-safe clock binding (core: world_clock_binding is thread-safe #640);
• the world_units unit registry with SI ↔ normalized-frame conversions (feat(core): unit registry for world_units; per-dimension display units; SI <-> nav's normalized frame #632);
• cvc::physics with the Jolt backend (physics: cvc::physics facade with null and Jolt backends; state-tree binding (vehicle physics P1) #641);
• the material trainer on the kinematic bicycle, with its pycvc bindings (nav: the material trainer on the kinematic bicycle (P8b, first item) #642).

Bumps project(VERSION) 3.5.1 → 3.6.0 and every cvcpkg recipe's upstream_version to match. cvc_revision stays 1, per the recipe-version gate, the same shape as #590.

The v3.6.0 tag goes on master only after #641 and #642 have merged. That tag runs release.yml (the GitHub Release and SDKs) and publish-cvcpkg.yml (libcvc, cvcgl, pycvc-cp311/312/313, pycvc-gl, cvc-cli on cvcpkg.org).