v0.6.0

Added

• bindings.json now carries vars — the baked plain values a sprout was
  built with — so the control plane can show what a version was compiled
  against. They ride along for display only; the broker never serves them,
  they are compiled into the sprout itself. A project whose only binding
  config is vars now gets a sidecar written at all, where before it got
  none.

Changed

• Tooling only, no change to how the CLI behaves: the tree is now formatted
  with oxfmt 0.66.0 (the config landed in 0.5.0 but was never run over the
  tree), markdown is excluded from formatting, a lefthook pre-commit hook
  formats staged files and lints, the last 10 oxlint warnings are cleared,
  and CI gates lint alongside typecheck and test.
• README rewritten shorter: a logo lockup that survives both GitHub themes
  (docs/logo-light.svg / docs/logo-dark.svg behind a <picture>), the
  everyday commands as a five-row table, and the full command inventory left
  to the generated SURFACE.md instead of duplicated by hand.