http: requireRole middleware + 403 forbidden page

web/templates/pages/forbidden.html

@@ -0,0 +1,21 @@
+{{define "title"}}Forbidden · restic-manager{{end}}
+
+{{define "content"}}
+{{$page := .Page}}
+<div class="max-w-[1280px] mx-auto px-8 pb-14">
+  <div class="crumbs pt-6">
+    <a href="/">Dashboard</a><span class="sep">/</span>
+    <span class="text-ink-mid">forbidden</span>
+  </div>
+  <div class="panel mt-8 rounded-[7px] p-8 max-w-[640px]"
+       style="border-color: color-mix(in oklch, var(--bad), transparent 60%);">
+    <div class="text-[14px] font-medium text-bad mb-2">403 — Insufficient role</div>
+    <p class="text-pretty text-[12.5px] text-ink-mute leading-[1.6]">
+      Your role (<span class="mono">{{$page.Have}}</span>) does not permit
+      this page (<span class="mono">{{$page.Required}}</span> required).
+      Ask your administrator if you need access.
+    </p>
+    <a href="/" class="btn btn-primary mt-5">Back to dashboard</a>
+  </div>
+</div>
+{{end}}