Allowing unauthenticated users to see scopes

app/templates/_nav.html

@@ -1,11 +1,12 @@
-{% set su = user.is_superuser %}
-{% set p = user.permissions %}
+{% set su = user.is_superuser if user else False %}
+{% set p = user.permissions if user else [] %}
 {% set can_admin = su or "users:read" in p or "roles:read" in p or "audit_log:read" in p %}
 {% set can_connections = su or "clamp_connections:read" in p or "iso_threads:read" in p or "static_connections:read" in p or "unc_threads:read" in p %}
 {% set can_labels = su or "attachment_point_names:read" in p or "manufacturers:read" in p or "part_colours:read" in p or "part_types:read" in p or "scope_models:read" in p or "sub_part_types:read" in p %}
 {% set can_database = su or "imported_parts:read" in p or "augmented_parts:read" in p or "attachment_points:read" in p %}
 {% set can_parts = can_connections or can_labels or can_database %}
-{% set can_scopes = su or ("augmented_parts:read" in p and "fits:read" in p) %}
+{# /scopes is public, so anonymous visitors see the link too; logged-in users still need the read perms. #}
+{% set can_scopes = (not user) or su or ("augmented_parts:read" in p and "fits:read" in p) %}
 
 {# ── SVG icon sprite ───────────────────────────────────────────────────────── #}
 <svg xmlns="http://www.w3.org/2000/svg" style="display:none">
@@ -232,8 +233,12 @@
 
     <a href="/docs" target="_blank">{{ icon("book-open") }} API docs</a>
   </nav>
+  {% if user %}
   <form method="post" action="/logout" class="logout">
     <span class="muted">{{ user.email }}</span>
     <button type="submit" class="btn btn-ghost">Sign out</button>
   </form>
+  {% else %}
+  <a href="/login" class="btn btn-ghost">Sign in</a>
+  {% endif %}
 </header>