Add menu bar display mode selector (5h, 7d, Auto)

Fix app icon for notifications, bump to v1.1.0

Improve sparkline: 24h history, 5min sampling, time axis labels

Improve README: tighter structure, screenshots below fold, smaller popover image

Add screenshots to README and fix clone URL

Add custom app icon: orange sparkle on dark background

Add 5hr reset countdown, adaptive refresh, notifications, sparkline, and UI polish

Initial commit: ClaudeUsageBar macOS menu bar app