Initial commit: Paperwall, a standalone e-ink dashboard

Navidrome now-playing, clock, and weather for a Waveshare epd4in0e panel,
with a local web UI and install/uninstall scripts for the Pi.

web/templates/settings_rotation.html

@@ -0,0 +1,29 @@
+{% extends "base.html" %}
+{% block content %}
+<h1>Rotation</h1>
+
+<form method="post">
+  <div class="field">
+    <label>Navidrome takes over when music plays</label>
+    <label class="checkbox">
+      <input type="checkbox" name="navidrome_priority" {{ "checked" if navidrome_priority }}>
+      Show Navidrome immediately whenever something is playing, regardless of rotation
+    </label>
+  </div>
+
+  <div class="field">
+    <label for="screens">Rotation order (used when Navidrome isn't playing, or if priority is off)</label>
+    <input type="text" id="screens" name="screens" value="{{ rotation.screens | join(', ') }}" placeholder="clock, weather">
+    <p style="font-size:0.8rem;color:#666">
+      Comma-separated, in order. Available: {{ screens.keys() | join(', ') }}.
+    </p>
+  </div>
+
+  <div class="field">
+    <label for="interval_seconds">Rotation interval (seconds)</label>
+    <input type="number" id="interval_seconds" name="interval_seconds" value="{{ rotation.interval_seconds }}" min="10">
+  </div>
+
+  <button type="submit">Save</button>
+</form>
+{% endblock %}