✨ 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.

AGENTS.md

@@ -67,3 +67,23 @@ Tibi CMS starter template — Svelte 5 SPA with esbuild, SSR via goja, and Playw
 - Avoid introducing new dependencies unless absolutely necessary.
 - Respect a11y and localization best practices; optimize for WCAG AA standards.
 - Check the problems tab for any errors or warnings in the code.
+- **Zero warnings policy**: After making changes, always run `yarn validate` and check the IDE problems tab. Fix all TypeScript, Svelte, and Tailwind warnings — the codebase must stay warning-free.
+- When Tailwind `suggestCanonicalClasses` warnings appear, always fix the **source** `.svelte`/`.ts`/`.css` file — never the compiled output.
+
+### Tailwind CSS 4 canonical classes
+
+This project uses Tailwind CSS 4. Always use the canonical v4 syntax:
+
+| Legacy (v3)            | Canonical (v4)         |
+| ---------------------- | ---------------------- |
+| `bg-gradient-to-*`     | `bg-linear-to-*`       |
+| `aspect-[4/3]`         | `aspect-4/3`           |
+| `!bg-brand-600`        | `bg-brand-600!`        |
+| `hover:!bg-brand-700`  | `hover:bg-brand-700!`  |
+| `!rounded-xl`          | `rounded-xl!`          |
+
+Rules:
+
+- Gradient directions use `bg-linear-to-{direction}` instead of `bg-gradient-to-{direction}`.
+- Bare-ratio aspect values like `aspect-4/3` replace arbitrary `aspect-[4/3]`.
+- The `!important` modifier is a **suffix** (`class!`) instead of a **prefix** (`!class`).