[Toolkit] Restore the "available since" note on recipe install steps

| Q              | A
| -------------- | ---
| Bug fix?       | yes
| New feature?   | no
| Deprecations?  | no
| Documentation? | no
| Issues         | Fix #3857
| License        | MIT

Reported in #3857: a Toolkit recipe that's merged but not yet tagged shows up in the documentation with nothing to say it can't be installed yet, so running `php bin/console ux:install form` fails with `The recipe "form" does not exist in any official kit` and gives no clue why.

The docs used to carry a note reading `Available since UX Toolkit X.Y.`, built from the `version-added` field each recipe manifest declares. It got lost when kit documentation became generic: the per-recipe template that held the note went away, and the `::: installation` directive that replaced it never carried it over. This restores it in `_installation.md.twig`, for both the plain Markdown output and the tabbed HTML one.

The `login-01` and `login-02` blocks, both added after `v3.4.0`, had no `version-added` at all, so they'd have stayed silent even with the note restored; they now declare `3.5`. Nothing was holding the note in place before, which is how it disappeared without a test turning red, so there's now a test covering both output formats plus a recipe that declares no version.

Author: Kocal

src/Toolkit/kits/shadcn/login-01/manifest.json

@@ -1,6 +1,7 @@
 {
     "$schema": "../../../schema-kit-recipe-v1.json",
     "type": "block",
+    "version-added": "3.5",
     "name": "LoginForm",
     "description": "A simple login form centered in a card.",
     "copy-files": {

src/Toolkit/kits/shadcn/login-02/manifest.json

@@ -1,6 +1,7 @@
 {
     "$schema": "../../../schema-kit-recipe-v1.json",
     "type": "block",
+    "version-added": "3.5",
     "name": "LoginForm",
     "description": "A two-column login page with a cover image.",
     "copy-files": {

src/Toolkit/templates/doc/_installation.md.twig

@@ -1,4 +1,9 @@
 {% if format == 'markdown' %}
+{% if recipe.manifest.versionAdded is not null %}
+> [!NOTE]
+> Available since UX Toolkit {{ recipe.manifest.versionAdded }}.
+
+{% endif %}
 ```shell
 php bin/console ux:install {{ recipe.name }} --kit {{ kit_id }}
 ```
@@ -7,6 +12,11 @@ php bin/console ux:install {{ recipe.name }} --kit {{ kit_id }}
 
 :: tab Automatic
 
+{% if recipe.manifest.versionAdded is not null %}
+> [!NOTE]
+> Available since UX Toolkit {{ recipe.manifest.versionAdded }}.
+
+{% endif %}
 ```shell
 php bin/console ux:install {{ recipe.name }} --kit {{ kit_id }}
 ```

src/Toolkit/tests/Doc/RecipeDocRendererTest.php

@@ -48,16 +48,28 @@ public function testRenderAsMarkdownResolvesExamplesAndOmitsInteractiveDirective
         $this->assertStringContainsString('<twig:PostLink>', $markdown);
     }
 
+    public function testTheInstallStepsAnnounceTheVersionTheRecipeWasAddedIn(): void
+    {
+        [$kit, $recipe] = $this->loadPostLinkRecipe();
+        $markdown = $this->renderer()->renderAsMarkdown($kit, $recipe);
+        $this->assertStringContainsString('Available since UX Toolkit 3.4.', $markdown);
+
+        $urlGenerator = $this->previewUrlGenerator();
+
+        $rendered = $this->renderer()->renderAsHtml($kit, $recipe, $urlGenerator);
+        $this->assertStringContainsString('Available since UX Toolkit 3.4.', $rendered->html);
+
+        // A recipe that declares no version says nothing.
+        [$kit, $recipe] = $this->loadWidgetRecipe();
+        $this->assertNull($recipe->manifest->versionAdded);
+        $this->assertStringNotContainsString('Available since UX Toolkit', $this->renderer()->renderAsMarkdown($kit, $recipe));
+    }
+
     public function testRenderAsHtmlProducesTabsAndALivePreview(): void
     {
         [$kit, $recipe] = $this->loadPostLinkRecipe();
 
-        $urlGenerator = new class implements PreviewUrlGenerator {
-            public function generate(string $code, CodeOptions $options): ?string
-            {
-                return 'https://preview.test/render';
-            }
-        };
+        $urlGenerator = $this->previewUrlGenerator();
 
         $rendered = $this->renderer()->renderAsHtml($kit, $recipe, $urlGenerator);
 
@@ -126,12 +138,7 @@ public function testRenderAsHtmlIncludesStimulusControllerApiReference(): void
     {
         [$kit, $recipe] = $this->loadWidgetRecipe();
 
-        $urlGenerator = new class implements PreviewUrlGenerator {
-            public function generate(string $code, CodeOptions $options): ?string
-            {
-                return 'https://preview.test/render';
-            }
-        };
+        $urlGenerator = $this->previewUrlGenerator();
 
         $html = $this->renderer()->renderAsHtml($kit, $recipe, $urlGenerator)->html;
 
@@ -153,12 +160,7 @@ public function testHtmlInstallationStepsCarryTheFileNameInTheInfoString(): void
         // A doc with only the install directive: no previews/alerts, so a small environment is enough.
         $recipe = new Recipe($recipe->name, $recipe->absolutePath, $recipe->manifest, doc: "## Installation\n\n::: installation");
 
-        $urlGenerator = new class implements PreviewUrlGenerator {
-            public function generate(string $code, CodeOptions $options): ?string
-            {
-                return null;
-            }
-        };
+        $urlGenerator = $this->previewUrlGenerator(null);
 
         // Mirror the host: a fenced-code renderer that surfaces the info string so we can assert the
         // filename travels with the block (as ux.symfony.com's renderer reads it back).
@@ -179,6 +181,20 @@ public function render(Node $node, ChildNodeRendererInterface $childRenderer): s
         $this->assertStringContainsString('&quot;filename&quot;:&quot;templates/components/PostLink.html.twig&quot;', $html);
     }
 
+    private function previewUrlGenerator(?string $url = 'https://preview.test/render'): PreviewUrlGenerator
+    {
+        return new class($url) implements PreviewUrlGenerator {
+            public function __construct(private ?string $url)
+            {
+            }
+
+            public function generate(string $code, CodeOptions $options): ?string
+            {
+                return $this->url;
+            }
+        };
+    }
+
     private function renderer(): RecipeDocRenderer
     {
         return new RecipeDocRenderer(self::getContainer()->get('twig'));