feat: sitemap settings singleton with content types and additional addresses

- one settings tile opening the golem15.sitemap.settings singleton
- Files tab (site address, file size, S1 files partial), Additional
  addresses repeater, Content types tab built from signpost at boot
- golem15_sitemap_types; a type switched off leaves the files (reason type)
- a save validates (errors.*) and dispatches a rebuild after commit

controllers/settings/_sitemap_files.htm

@@ -0,0 +1,42 @@
+{{- if .Data.Building -}}
+<div class="summer-callout" role="status">
+<p class="summer-callout__text">{{ trans "golem15.sitemap::lang.files.building" }}</p>
+</div>
+{{- end -}}
+{{- if .Data.Empty -}}
+<div class="summer-callout" role="status">
+<p class="summer-callout__text">{{ trans "golem15.sitemap::lang.files.empty" }}</p>
+</div>
+{{- else -}}
+<section>
+<h4>{{ trans "golem15.sitemap::lang.files.label" }}</h4>
+<div class="summer-table-wrap">
+<table class="summer-table">
+<thead><tr><th>{{ trans "golem15.sitemap::lang.files.file" }}</th><th class="summer-table__num">{{ trans "golem15.sitemap::lang.files.file_urls" }}</th><th>{{ trans "golem15.sitemap::lang.files.file_lastmod" }}</th></tr></thead>
+<tbody>
+{{- range .Data.Files -}}
+<tr><td>{{ if .URL }}<a href="{{ .URL }}"><code>{{ .Name }}</code></a>{{ else }}<code>{{ .Name }}</code>{{ end }}</td><td class="summer-table__num">{{ .Count }}</td><td>{{ .LastMod }}</td></tr>
+{{- end -}}
+</tbody>
+</table>
+</div>
+</section>
+{{- end -}}
+{{- if .Data.LeftOut -}}
+<section>
+<h4>{{ trans "golem15.sitemap::lang.files.left_out" }}</h4>
+<div class="summer-table-wrap">
+<table class="summer-table">
+<thead><tr><th>{{ trans "golem15.sitemap::lang.files.left_out_reason" }}</th><th class="summer-table__num">{{ trans "golem15.sitemap::lang.files.left_out_count" }}</th></tr></thead>
+<tbody>
+{{- range .Data.LeftOut -}}
+<tr><td>{{ .Label }}</td><td class="summer-table__num">{{ .Count }}</td></tr>
+{{- end -}}
+</tbody>
+</table>
+</div>
+</section>
+{{- end -}}
+<div class="summer-callout" role="note">
+<p class="summer-callout__text">{{ .Data.Note }}</p>
+</div>

controllers/settings/config_form.yaml

@@ -0,0 +1,20 @@
+# ===================================
+#  Form Behavior Config
+# ===================================
+#
+# The sitemap settings singleton (UI-SPEC C26), linked from the sitemap
+# settings tile. The plugin's form extension adds the Content types tab
+# after Files.
+
+name: golem15.sitemap::lang.settings.label
+form: ~/plugins/golem15/sitemap/models/settings/fields.yaml
+modelClass: Golem15\Sitemap\Models\Settings
+defaultRedirect: system/settings
+
+update:
+    redirect: golem15/sitemap/settings
+    redirectClose: system/settings
+
+messages:
+    update: golem15.sitemap::lang.settings.label
+    saved: backend::lang.messages.form.saved