Initial release of Nikki.

• Full Memos API integration with offline sync
• Todoist-style task parsing from markdown checkboxes
• Due dates, times, priorities, reminders, and tags
• Parser doctor with inline validation and typo detection
• 4-channel priority notifications with calendar integration
• Windows Phone Metro design with 20 accent colors
• Activity calendar, tag browser, search, archived memos
• Share intent receiver for quick capture
• JSON backup/restore
• 162 tests passing
