Under the hood
Plugin validator now flags manifests that declare engine hook types but never register an engine.create hook
What
The validator that checks plugin manifests now compares a plugin's declared 'types contract' (which members it promises to implement on the engine interface) against what the plugin actually registers. If the manifest declares members on EngineInterface but the plugin never registers a handler for the engine.create event, a new diagnostic is now emitted.
Why
This catches plugins that describe capabilities in their manifest but never actually wire them up, surfacing a mismatch that would otherwise go unnoticed until the plugin failed to behave as declared.