release: v0.31.0 — family-contacts integration & settings restructure

- Family member records now store phone, email, and birthday, auto-synced
  to Contacts and Birthdays modules (PR #99 by @rafaelfoster)
- Settings gets dedicated Family and API Tokens tabs (admin-only)
- Avatar editor redesigned with icon buttons; tab bar fits standard width
- Dentist calendar icon normalised to 'tooth'; theme reset bug fixed
- i18n: missing family field translations added to 12 locales

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

public/locales/ja.json

@@ -734,13 +734,13 @@
         "shared": "共有"
       }
     },
-    "memberPhoneLabel": "Phone number (optional)",
-    "memberEmailLabel": "Email (optional)",
-    "memberBirthDateLabel": "Birthday date (optional)",
-    "memberContactBirthdayHint": "This member is automatically synchronized with Contacts and Birthdays.",
-    "memberBirthDateInvalid": "Use a valid birthday date in the selected date format.",
-    "memberPhoneMeta": "Phone: {{value}}",
-    "memberBirthdayMeta": "Birthday: {{date}}"
+    "memberPhoneLabel": "電話番号（任意）",
+    "memberEmailLabel": "メールアドレス（任意）",
+    "memberBirthDateLabel": "生年月日（任意）",
+    "memberContactBirthdayHint": "このメンバーは連絡先と誕生日と自動的に同期されます。",
+    "memberBirthDateInvalid": "選択した日付形式で有効な生年月日を入力してください。",
+    "memberPhoneMeta": "電話: {{value}}",
+    "memberBirthdayMeta": "誕生日: {{date}}"
   },
   "login": {
     "tagline": "家族計画。安全。プライバシー重視。オープンソース。",