feat(interfaces): add structured data models and discriminated check configs; migrate tooling and package metadata

ts/data/checks/assumption.check.ts

@@ -1,6 +1,11 @@
-import * as plugins from '../../ul-interfaces.plugins.js';
-import { TCheckResultStatus, TExecutionTiming } from './index.js';
+import type * as plugins from '../../ul-interfaces.plugins.js';
+import type { TCheckResultStatus } from '../types.js';
+import type { TExecutionTiming } from './index.js';
 
+/**
+ * Assumption check execution data.
+ * Used by check runners to store input and results.
+ */
 export interface IAssumptionCheck {
   inputData: {
     domain: string;