Add version chip (v0.1.0) + changelog

- version.py: __version__ = 0.1.0 + structured CHANGELOG (newest first).
- footer version chip on every page (base.html) links to /changelog.
- /changelog page renders release notes; CHANGELOG.md mirrors it.
- 0.1.0 captures the storage/SQLite/settings/suggestions/backup work.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

templates/changelog.html

@@ -0,0 +1,19 @@
+{% extends "base.html" %}
+{% block content %}
+<div style="max-width:720px;">
+  <h1>📒 What's New</h1>
+  <p style="color:#7A6E68;margin-bottom:1.25rem;">Current version: <strong>v{{ app_version }}</strong></p>
+
+  {% for rel in changelog %}
+  <div style="border:1px solid #EDE8E2;border-radius:10px;padding:1rem 1.25rem;margin-bottom:1rem;">
+    <div style="display:flex;align-items:baseline;gap:.6rem;flex-wrap:wrap;">
+      <h2 style="margin:0;font-size:1.1rem;">v{{ rel.version }}</h2>
+      <span style="color:#B0A89E;font-size:.85rem;">{{ rel.date }}{% if rel.title %} · {{ rel.title }}{% endif %}</span>
+    </div>
+    <ul style="margin:.6rem 0 0;padding-left:1.2rem;">
+      {% for c in rel.changes %}<li style="margin:.3rem 0;">{{ c }}</li>{% endfor %}
+    </ul>
+  </div>
+  {% endfor %}
+</div>
+{% endblock %}