Rewrite server: FastAPI + auth (users/roles/tokens) + admin WebUI + server-authoritative covers/metadata

server/templates/login.html

@@ -0,0 +1,13 @@
+{% extends "base.html" %}
+{% block title %}Login · psppt{% endblock %}
+{% block content %}
+<div class="card narrow">
+  <h1>psppt server</h1>
+  {% if error %}<p class="error">{{ error }}</p>{% endif %}
+  <form method="post" action="/login">
+    <label>Username <input name="username" required autofocus></label>
+    <label>Password <input name="password" type="password" required></label>
+    <button>Log in</button>
+  </form>
+</div>
+{% endblock %}