Landing page for NSFW content, SFW-only mode (#656)

Co-authored-by: Matt <matt@matthew.science>
Co-authored-by: Spike <19519553+spikecodes@users.noreply.github.com>

templates/settings.html

@@ -54,6 +54,7 @@
 						{% call utils::options(prefs.comment_sort, ["confidence", "top", "new", "controversial", "old"], "confidence") %}
 					</select>
 				</div>
+        {% if !crate::utils::sfw_only() %}
 				<div class="prefs-group">
 					<label for="show_nsfw">Show NSFW posts:</label>
 					<input type="hidden" value="off" name="show_nsfw">
@@ -64,6 +65,7 @@
 					<input type="hidden" value="off" name="blur_nsfw">
 					<input type="checkbox" name="blur_nsfw" id="blur_nsfw" {% if prefs.blur_nsfw == "on" %}checked{% endif %}>
 				</div>
+        {% endif %}
 				<div class="prefs-group">
 					<label for="autoplay_videos">Autoplay videos</label>
 					<input type="hidden" value="off" name="autoplay_videos">
@@ -121,6 +123,10 @@
 	<div id="settings_note">
 		<p><b>Note:</b> settings and subscriptions are saved in browser cookies. Clearing your cookies will reset them.</p><br>
 		<p>You can restore your current settings and subscriptions after clearing your cookies using <a href="/settings/restore/?theme={{ prefs.theme }}&front_page={{ prefs.front_page }}&layout={{ prefs.layout }}&wide={{ prefs.wide }}&post_sort={{ prefs.post_sort }}&comment_sort={{ prefs.comment_sort }}&show_nsfw={{ prefs.show_nsfw }}&blur_nsfw={{ prefs.blur_nsfw }}&use_hls={{ prefs.use_hls }}&hide_hls_notification={{ prefs.hide_hls_notification }}&subscriptions={{ prefs.subscriptions.join("%2B") }}&filters={{ prefs.filters.join("%2B") }}">this link</a>.</p>
+		<br />
+		{% if crate::utils::sfw_only() %}
+		<p>This instance is SFW-only. It will block all NSFW content.</p>
+		{% endif %}
 	</div>
 </div>