test: add component tests for the administration client

.github/workflows/ci.yml

@@ -55,6 +55,7 @@ jobs:
         run: |
           npm ci
           npm run typecheck
+          npm test
           npm run build
 
       - name: Verify generated client assets

CONTRIBUTING.md

@@ -49,6 +49,8 @@ for versioning and publishing steps.
    ```powershell
    cd src/XperienceCommunity.FormsToolkit/Client
    npm ci
+   npm run typecheck
+   npm test
    npm run build
    ```
 

docs/Contributing-Setup.md

@@ -72,9 +72,19 @@ When changing files under `src/XperienceCommunity.FormsToolkit/Client/src`, run:
 ```powershell
 cd src/XperienceCommunity.FormsToolkit/Client
 npm ci
+npm run typecheck
+npm test
 npm run build
 ```
 
+`npm test` runs the component tests (`*.test.tsx` next to each component) with
+Vitest and React Testing Library. The Kentico admin packages only run inside the
+Xperience administration, so the tests replace them with the test doubles in
+`Client/test/kentico`: `usePageCommand` returns responses set with
+`mockPageCommand` and records every payload in `pageCommandCalls`, and the admin
+components render plain, labelled HTML. When a component starts using another
+admin export, add a stand-in for it there.
+
 Commit the generated `Client/dist` assets with the source changes. Normal package
 consumers do not need Node.js because the built administration module is embedded
 in the Forms Toolkit assembly.