prepare app for public app store distribution

- rebrand from 습관 트래커 to 해빗랩 across templates, manifest, service worker
- add HTTPS redirect middleware for reverse-proxied deployments
- add public landing page (/) and privacy policy page with real data
  handling disclosures
- add in-app account deletion (Apple review requirement)
- add Android TWA Digital Asset Links support (/.well-known/assetlinks.json)
- add SFTP deployment script for the Synology-hosted server

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

app/templates/account.html

@@ -0,0 +1,24 @@
+{% extends "base.html" %}
+{% block title %}계정 · 해빗랩{% endblock %}
+{% block content %}
+<h1>계정</h1>
+
+<div class="card">
+  <p><strong>이메일</strong><br />{{ current_user.email }}</p>
+  {% if current_user.name %}<p><strong>이름</strong><br />{{ current_user.name }}</p>{% endif %}
+  <p><strong>가입일</strong><br />{{ current_user.created_at.strftime('%Y-%m-%d') }}</p>
+</div>
+
+<div class="card">
+  <h2>계정 삭제</h2>
+  <p>
+    계정을 삭제하면 등록한 모든 습관, 체크 기록, 알림 구독 정보가 즉시 영구적으로 삭제되며 되돌릴 수 없습니다.
+  </p>
+  {% if delete_error %}<p style="color: var(--color-danger);">{{ delete_error }}</p>{% endif %}
+  <form method="post" action="/account/delete">
+    <label for="confirm_email">확인을 위해 본인 이메일({{ current_user.email }})을 입력하세요</label>
+    <input type="text" id="confirm_email" name="confirm_email" autocomplete="off" />
+    <button type="submit" class="btn btn-danger-ghost btn-block" style="margin-top: var(--space-2);">계정 영구 삭제</button>
+  </form>
+</div>
+{% endblock %}