✨ feat: add new contact form, hero, features, and richtext blocks; implement scroll-reveal action and update styles

- Introduced ContactFormBlock, FeaturesBlock, HeroBlock, and RichtextBlock components.
- Implemented a scroll-reveal action for animations on element visibility.
- Enhanced CSS styles for better theming and prose formatting.
- Added localization support for new components and updated existing translations.
- Created e2e tests for demo pages including contact form validation and navigation.
- Added a video tour showcasing the demo pages and interactions.

frontend/src/blocks/BlockRenderer.svelte

@@ -0,0 +1,44 @@
+<script lang="ts">
+    /**
+     * BlockRenderer — renders ContentBlockEntry[] by type.
+     *
+     * Each block type maps to a dedicated Svelte component.
+     * Unknown types are silently skipped (or shown in dev mode).
+     * Easy to extend: add a new component import + case.
+     *
+     * DEMO: This file is part of the demo showcase.
+     * For real projects, adjust block types and components as needed.
+     */
+    import HeroBlock from "./HeroBlock.svelte"
+    import FeaturesBlock from "./FeaturesBlock.svelte"
+    import RichtextBlock from "./RichtextBlock.svelte"
+    import AccordionBlock from "./AccordionBlock.svelte"
+    import ContactFormBlock from "./ContactFormBlock.svelte"
+
+    let { blocks = [] }: { blocks: ContentBlockEntry[] } = $props()
+</script>
+
+{#each blocks as block, i (i)}
+    {#if !block.hide}
+        {#if block.type === "hero"}
+            <HeroBlock {block} />
+        {:else if block.type === "features"}
+            <FeaturesBlock {block} />
+        {:else if block.type === "richtext"}
+            <RichtextBlock {block} />
+        {:else if block.type === "accordion"}
+            <AccordionBlock {block} />
+        {:else if block.type === "contact-form"}
+            <ContactFormBlock {block} />
+        {:else}
+            <!-- Unknown block type: {block.type} -->
+            {#if typeof window !== "undefined" && window.location?.hostname === "localhost"}
+                <div
+                    class="max-w-6xl mx-auto px-6 py-4 bg-yellow-50 border border-yellow-200 rounded-lg my-4 text-sm text-yellow-800"
+                >
+                    Unknown block type: <code>{block.type}</code>
+                </div>
+            {/if}
+        {/if}
+    {/if}
+{/each}