add journaling feature: categories, tags, attachments, calendar, and multi-select emotions

Adds an 8th development stage that lets users keep a free-form journal alongside
habit tracking, reusing the existing Google OAuth/DB/PWA infrastructure instead
of a separate project. Users organize entries into custom categories, filter by
a month calendar with day-detail drill-down, attach photos/videos (served via an
authenticated route, never /static), tag entries, and pick multiple emotions per
entry from a curated 9-option set. Includes a global journal prompt bank for
lightweight guided journaling.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

pyproject.toml

@@ -19,12 +19,12 @@ dependencies = [
     "py-vapid>=1.9",
     "authlib>=1.3",
     "httpx>=0.27",
+    "pillow>=10.0",  # scripts/generate_icons.py 아이콘 재생성 + 저널 첨부 이미지 썸네일 생성(런타임)
 ]
 
 [project.optional-dependencies]
 dev = [
     "pytest>=8.0",
-    "pillow>=10.0",  # scripts/generate_icons.py 아이콘 재생성용 (런타임 미사용)
     "paramiko>=3.4",  # scripts/deploy_sftp.py SFTP 배포용 (런타임 미사용)
 ]