Discord-style sidebar + page routing

[realproject7]

Parent: #1 (Phase 1 — Batch 2)

Scope

Build the Discord-style left sidebar for navigating between home and project dashboards.

Tasks

• Sidebar component: 64px wide, fixed left, dark surface background (#111111)
• Home icon at top → navigates to /
• Project icons: circular, shows first letter or avatar, hover tooltip with project name
• Active project highlighted with accent border (#00ff88)
• Divider line between projects and actions
• + button → placeholder for add-project flow
• Settings gear icon at bottom → navigates to /settings
• App Router pages: / (home), /project/[id] (project dashboard), /settings
• Sidebar persists across all pages

Design

• Sharp corners on sidebar, thin right border (1px solid #2a2a2a)
• Icons: monospace text or simple SVG, no icon library
• Hover: subtle background change to #1a1a1a

Branch

task/4-sidebar-routing

Implementation Note

T3 MUST use the /frontend-design skill on Claude Code for all frontend/UI work in this ticket.