Port 4ducky to Rust (Axum + SQLite)

Same design, layout, URLs and features as the PHP version: browse grid,
image view with AJAX comments, BBCode, likes, uploads (file, URL and
bookmarklet), quicktagger, profile, block list, inbox, invites, Hall of
Ducks, Truhe, abuse reports and the admin tools.

- Parameterized SQL, escaped templates (askama), argon2 passwords,
  server-side sessions, CSRF tokens on every write, strict script CSP
- SSRF-safe remote image fetching, magic-byte upload checks
- Self-hosted captcha replaces reCAPTCHA v1; analytics/social widgets removed
- Vanilla JS replaces jQuery and its plugins with the same DOM behaviour
- Reverse proxy support (frontend_path, trust_proxy, secure_cookies)
- Admin CLI: admin, settings, invites

See README.md for running it and the full list of changes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

templates/userlist.html

@@ -0,0 +1,44 @@
+{% include "header.html" %}
+<h1>
+	&raquo; Browsing Users,
+	Page: {{ current }} of {{ total }}
+</h1>
+
+{%- for u in users %}
+	<div class="userInfo" style=" {{ border }} ">
+		<img class="avatar" width="40" height="40" src="/{{ u.avatar }}"/>
+		<div class="name">
+			<strong>
+				<a href="/user/{{ u.name_enc }}">{{ u.name }}</a>
+			</strong>
+		</div>
+		<div class="info">
+
+			Images: <strong>{{ u.images }}</strong>
+			{%- if let Some(w) = u.website %}|
+				<strong><a href="{{ w }}" target="_blank">
+					Website
+				</a></strong>
+			{%- endif %}
+		</div>
+		<div style="clear:both;"></div>
+	</div>
+{%- endfor %}
+
+<div class="userInfo">
+	{%- if let Some(p) = prev %}
+		<a href="/users/page/{{ p }}" class="textPrev" title="Previous">&laquo; Previous</a>
+	{%- else %}
+		<div class="textNoPrev">&laquo; Previous</div>
+	{%- endif %}
+
+	{%- if let Some(n) = next %}
+		<a href="/users/page/{{ n }}" class="textNext" title="Next">Next &raquo;</a>
+	{%- else %}
+		<div class="textNoNext">Next &raquo;</div>
+	{%- endif %}
+
+	<div style="clear: both;"></div>
+</div>
+
+{% include "footer.html" %}