v0.2.0

A key can declare which scopes it is decided along.

scopes: [homelab, cloud, effect-stack]
keys:
  cni.routing-mode:
    scopes: [homelab, cloud]

A scope list can span more than one axis. Clusters, landscapes and stack
families are all scopes and none of them are interchangeable, so a single flat
list made scope-declared unable to reject cni.routing-mode@effect-stack —
and §5 fallback then answered it from the default scope. That is an active
verdict about a different question, which reads as agreement. This is the change
the fleet corpus needs before it can hold decisions from more than one axis.

• An entry deciding a key outside its declared scopes is a new Layer A check,
  scope-applies.
• A query at such a scope returns unknown (exit 7) and never falls back. Its
  JSON payload carries applies_to, the axis the caller should have asked on,
  in place of a did-you-mean.
• The default scope stays admitted whatever a key declares, so restricting a key
  cannot sever its own fallback.
• A key with no scopes accepts every declared scope, so every existing
  registry keeps its meaning. An empty list is not the same as absent: it says
  the key is decided fleet-wide only.

Spec: SEMANTICS section 2.1. Four conformance cases and a scoped-keys corpus.

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What's Changed

• fix: installer described amont's hooks, not aval by @fredericrous in #4
• feat: a key declares which scopes it applies to by @fredericrous in #5

Full Changelog: v0.1.1...v0.2.0