Keep canonical availability states and legacy booleans consistent at every dashboard boundary

Reusable finding from COR-4110: when a dashboard introduces canonical availability states alongside a legacy supported boolean, selection, filtering, labels, empty states, and compatibility fixtures must apply the same precedence rules. A check can have an executable adapter while still being non-runnable because required data or access is missing; tests that intentionally emulate legacy promotion must update both representations or use a narrowly documented compatibility path. This prevented unavailable checks from entering run plans and prevented runnable empty states from being misleading.

Observed 2026-09-09T02:54:00Z from the combined ender-inference dashboard diff and 158 focused dashboard/workspace tests. Source: COR-4110, commit 2c240462e952d4afb80195cee889b9551dec98a9, https://github.com/e3-solutions/ender-inference/pull/170.