Introduce a persistent left sidebar, update navigation to support regions, and convert the UI to a flat/no-blur visual style.
Key changes:
- index.html: add a persistent sidebar markup with nav items, user area and main app layout.
- src/core/nav.js: improve candidate scoring to use element bounding centers and overlap penalty; include extra focus roots; add region metadata handling, helpers for resolving default content/sidebar indices, and special-case movements between sidebar and content; respect contract.useNebulaNavigation flag.
- src/main.js: manage sidebar visibility for full-screen flows (lock/onboarding), update sidebar active state on view changes, include sidebar as an extraFocusRoot when appropriate, and handle sidebar item activation on accept to navigate views.
- src/styles/*: major visual/theme updates to remove blur/glow effects (Zero-Blur policy), add flat sidebar styles, update components to solid borders and simpler focus styling, adjust theme variables (palette, spacing, durations), and redesign the home view layout and controls.
Rationale: provide a persistent, keyboard/controller-friendly sidebar for quick navigation while simplifying visuals to a flat, performance-friendly theme and refining focus/navigation behavior across sidebar and content regions.
Introduce a working v0 Nebula Shell prototype (Tauri frontend) and redesign docs. Adds a complete frontend under src/ (views: home, lock, library, settings, overlays), core adapters (input, nav, passkey, router, state), global styles and shell guidelines, and view-specific HTML/CSS/JS. Update README with prototype notes, install/run/build instructions and controller testing tips. Update package.json to add dev/build scripts and add @nebulaproject/core as a dependency. Also include a detailed REDESIGN_DOCUMENTATION.md describing the Xbox-inspired horizontal dashboard, component patterns, and developer notes.
andrew