Feature: Build branded docs home page instead of root redirect

[hdcodedev]

Summary

Create a branded docs landing page instead of immediate root redirect.

Why

/ currently redirects directly to versioned wiki, which removes the first-impression opportunity for visual identity.

Scope

• Design and implement a lightweight branded homepage.
• Include clear primary actions (Start Docs, API, Demo, GitHub).
• Surface current stable version and snapshot status.
• Keep SEO metadata aligned.

Acceptance Criteria

• Root path renders a real page (no immediate redirect).
• Page reflects chosen visual direction and typography/color system.
• Main entry actions are obvious and keyboard accessible.

[hdcodedev]

Closed — addressed or superseded by modernization work in #44.