Task 01: Create a clean, modern app shell with navigation, routing, and placeholder pages.
Scope:
- Collapsible sidebar with Dashboard, Projects, Reports, Workload
- Top bar with app name and sidebar toggle (collapsed by default)
- Projects list at /projects with mock data
- Project detail at /projects/:id
- Placeholder pages for Dashboard, Reports, Workload
- Search field and Logout button in sidebar footer
- App-level light/dark theme switcher in the shell
Subtasks:
- create 00-project-architecture.md
- create build-log.md and append the full request and full response after each task completion
Rules:
- keep this step shell-only
- keep routing and shell structure clear and reusable