Coerce a node's raw layer attr into "exposed in the Layers panel".
The Python writer (validate_layer) always normalises to a JSON boolean,
but hand-edited or third-party zarr may carry a number (1/0). Accept
strict true and truthy finite numbers so such values don't silently drop
the node from the panel; everything else (incl. undefined, strings) is
not-a-layer. Pure — callers log a warning for malformed (non-boolean) values.
Coerce a node's raw
layerattr into "exposed in the Layers panel".The Python writer (
validate_layer) always normalises to a JSON boolean, but hand-edited or third-party zarr may carry a number (1/0). Accept stricttrueand truthy finite numbers so such values don't silently drop the node from the panel; everything else (incl.undefined, strings) is not-a-layer. Pure — callers log a warning for malformed (non-boolean) values.