Implements website feature branch `407-msp-mittelstand-use-case-pages` into `website-dev`.
Summary:
- add German and English MSP and internal IT use-case landing pages
- expose localized buyer-path teasers from the homepage and platform page
- extend smoke coverage for the new routes, navigation links, metadata, and conservative claim checks
- include the aligned Spec Kit artifacts under `specs/407-msp-mittelstand-use-case-pages`
Validation:
- `cd apps/website && corepack pnpm build`
- `cd apps/website && corepack pnpm test -- tests/smoke/public-routes.spec.ts tests/smoke/interaction.spec.ts`
Follow-up integration path after merge:
`website-dev` -> `dev`.
Co-authored-by: Ahmed Darrazi <ahmed.darrazi@live.de>
Reviewed-on: #402
## Summary
- apply public website launch readiness updates across the Astro site shell, content, and navigation
- refine website components, metadata, and localization-related structure for launch prep
- update docs/content paths and smoke coverage to match the launch-ready public site state
## Scope
- touches the website app and related spec artifacts for feature 403
- does not modify `apps/platform`
## Testing
- not run in this step
Co-authored-by: Ahmed Darrazi <ahmed.darrazi@live.de>
Reviewed-on: #394
