feat(unit): export base type abstractions

Export Mocked<T> and Stub types from @suites/unit to establish the
abstraction layer of the abstraction/augmentation pattern.

These base types provide graceful fallback when adapter packages are
not configured, and serve as the foundation that adapter packages will
augment with library-specific implementations.

Author: omermorad

packages/unit/src/index.ts

@@ -1,8 +1,10 @@
 export { TestBed } from './testbed';
-export type { UnitTestBed, TestBedBuilder } from './types';
 export type {
-  UnitReference,
-  MockOverride,
+  UnitTestBed,
+  TestBedBuilder,
+  Mocked,
   SolitaryTestBedBuilder,
   SociableTestBedBuilder,
-} from '@suites/core.unit';
+} from './types';
+export type { UnitReference, MockOverride } from '@suites/core.unit';
+export type { Stub } from '@suites/types.doubles';

packages/unit/src/types.ts

@@ -8,6 +8,15 @@ import type {
   MockOverride as MockOverrideCore,
 } from '@suites/core.unit';
 
+/**
+ * Base abstract type for mocked instances. Adapters can augment this with
+ * library-specific implementations (Jest, Vitest, Sinon) via module augmentation.
+ *
+ * @template T The type being mocked
+ * @since 3.1.0
+ */
+export type Mocked<T> = StubbedInstance<T>;
+
 export interface SociableTestBedBuilder<TClass> extends SociableTestBedBuilderCore<TClass> {
   /**
    * Exposes a dependency to be included in the test environment in its real or partially mocked state.