Initial commit: Quiet Thanks gratitude app

A calm, private gratitude and mood log built with Next.js 16, TypeScript,
Tailwind CSS, and SQLite/Drizzle ORM.

Features:
- Quick check-in with autosave (800ms debounce)
- Optional mood selector (5 levels) with accessibility labels
- Optional tags with tap-to-add from recent
- Timeline with weekly reflection card
- Filters by mood, tag, and rough day
- Export to Markdown and JSON
- Dark mode default
- Delete with undo toast
- Docker deployment ready

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

public/icons/icon.svg

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