Give the backups plugin a settings page, and show where a snapshot is

plugins/backups/frontend/views/BackupsSettings.vue

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+<template>
+  <div>
+    <div class="page-header">
+      <h2>Backups</h2>
+    </div>
+
+    <div class="section-card">
+      <div class="setting-group">
+        <h3>Collection</h3>
+        <p class="setting-description">
+          How often a PC attempts to capture the config it backs up. GE-Enforce runs every
+          cycle, so this is what stops a bay collecting several times a day. A capture that
+          finds nothing changed writes no revision - it only records that the check happened.
+        </p>
+
+        <div class="setting-row">
+          <label>
+            <span>Interval (hours)</span>
+            <input type="number" min="1" v-model="values.backups_intervalhours"
+                   @blur="save('backups_intervalhours')" :disabled="saving">
+            <small class="input-hint">Default 24. Read by the fleet from /api/settings/public.</small>
+          </label>
+        </div>
+
+        <div class="setting-row">
+          <label>
+            <span>Share root (UNC)</span>
+            <input type="text" v-model="values.backups_shareroot"
+                   placeholder="\\fileserver\shopfloor\backup"
+                   @blur="save('backups_shareroot')" :disabled="saving">
+            <small class="input-hint">
+              Where opaque backups (part-marker snapshots) are written by the collecting PC.
+              Blank until the site sets it - no default is right at more than one site.
+              Advisory: each revision records the path it was actually written to.
+            </small>
+          </label>
+        </div>
+      </div>
+    </div>
+
+    <div class="section-card">
+      <div class="setting-group">
+        <h3>Health</h3>
+        <p class="setting-description">
+          A backup is judged on when it was last CONFIRMED, not when it last changed. An
+          unchanged config writes no revision, so a machine stable for months is healthy -
+          the one to worry about is the machine whose backup stopped running.
+        </p>
+
+        <div class="setting-row">
+          <label>
+            <span>Stale after (days)</span>
+            <input type="number" min="0" v-model="values.backups_staledays"
+                   @blur="save('backups_staledays')" :disabled="saving">
+            <small class="input-hint">
+              Default 3. Drives the fleet Backup badge and the dashboard card. 0 disables both.
+            </small>
+          </label>
+        </div>
+      </div>
+    </div>
+
+    <div class="section-card">
+      <div class="setting-group">
+        <h3>Retention</h3>
+        <p class="setting-description">
+          Both off by default, and dedup already keeps growth low - a revision appears only
+          when a config really changed. Retention exists for a value that flaps. The newest
+          and oldest revision of a chain are never pruned.
+        </p>
+        <p class="setting-description">
+          <strong>Note:</strong> pruning removes database revisions only. Files written to the
+          share are not deleted, so enabling this on a share-backed kind leaves snapshot
+          directories with no revision pointing at them.
+        </p>
+
+        <div class="setting-row">
+          <label>
+            <span>Keep at most (revisions per chain)</span>
+            <input type="number" min="0" v-model="values.backups_retentioncount"
+                   @blur="save('backups_retentioncount')" :disabled="saving">
+            <small class="input-hint">0 = keep everything.</small>
+          </label>
+        </div>
+
+        <div class="setting-row">
+          <label>
+            <span>Also drop older than (days)</span>
+            <input type="number" min="0" v-model="values.backups_retentiondays"
+                   @blur="save('backups_retentiondays')" :disabled="saving">
+            <small class="input-hint">0 = no age limit.</small>
+          </label>
+        </div>
+      </div>
+    </div>
+
+    <div v-if="error" class="error-message">{{ error }}</div>
+    <div v-if="success" class="settings-success">{{ success }}</div>
+  </div>
+</template>
+
+<script setup>
+// The backups plugin ships five settings and, until now, no page for any of
+// them - they were reachable only through the API or a flask shell on the
+// server. The core settings catalog is hardcoded and cannot be extended by a
+// plugin, so this page is contributed the ADR-010 way: a settings card from
+// get_settings_cards plus a route here, both of which disappear when the
+// plugin is disabled.
+import { ref, reactive, onMounted } from 'vue'
+import { settingsApi } from '@/api'
+import { apiError } from '@/utils/apiError'
+
+const KEYS = [
+  'backups_intervalhours',
+  'backups_shareroot',
+  'backups_staledays',
+  'backups_retentioncount',
+  'backups_retentiondays',
+]
+
+const values = reactive({})
+const saving = ref(false)
+const error = ref('')
+const success = ref('')
+
+async function load() {
+  try {
+    const response = await settingsApi.list()
+    const rows = response.data?.data || response.data || []
+    // The list endpoint returns every setting; pick out ours rather than
+    // fetching five times.
+    for (const key of KEYS) {
+      const row = rows.find(item => item.key === key)
+      values[key] = row ? row.value : ''
+    }
+  } catch (err) {
+    error.value = apiError(err, 'Could not load backup settings')
+  }
+}
+
+async function save(key) {
+  saving.value = true
+  error.value = ''
+  success.value = ''
+  try {
+    await settingsApi.update(key, values[key])
+    success.value = 'Saved'
+    setTimeout(() => { success.value = '' }, 2000)
+  } catch (err) {
+    error.value = apiError(err, `Could not save ${key}`)
+  } finally {
+    saving.value = false
+  }
+}
+
+onMounted(load)
+</script>