feat(cms): replace homepage latest-pages category text input with a channel-scoped selector

[jbourdin]

Bug / UX issue

In the homepage block editor, the category for a latestPages block is a free-form <TextInput> with placeholder "news". Editors must know the exact category name and type it manually. Typos silently produce an empty block (because HomepageRenderer::resolveLatestPages does a case-insensitive name match, and a miss returns no pages).

Current code

assets/components/BlockEditModal.tsx:185-201:

<TextInput
    label={label('categorySlug')}
    value={(editedBlock.categorySlug as string) ?? ''}
    onChange={(event) => updateBlock('categorySlug', event.currentTarget.value || null)}
    placeholder="news"
/>

src/Service/HomepageRenderer.php:185-215 resolves the category by case-insensitive English-name match — fragile if the category is renamed.

Fix

1. Add an admin endpoint that returns categories for the current channel (use existing MenuCategoryRepository::findAllOrdered($channel)).
2. Replace the <TextInput> with a Mantine <Select> (or <Autocomplete>) populated from that endpoint.
3. Store the category ID (or stable slug) in the block payload instead of the display name; update HomepageRenderer::resolveLatestPages to look up by ID/slug instead of name match.
4. Add a migration step to rewrite existing latestPages blocks to the new identifier.

Files

• assets/components/BlockEditModal.tsx:185-201
• src/Service/HomepageRenderer.php:185-215
• src/Entity/MenuCategory.php (channel relation already exists, lines 42-44)
• New admin controller endpoint (e.g. AdminHomepageController or a dedicated AdminMenuCategoryController)

Verification

1. Open the homepage block editor; the category field shows a dropdown of channel categories.
2. Select a category; save; reload the page editor — selection persists.
3. Render the homepage; the block shows pages from the selected category.
4. Renaming a category does not break the block (because we store the ID, not the name).