fix(operator): use refresh icon on Refresh buttons (was chevDown)

Every page header's Refresh button rendered a downward chevron because
the icon set had no refresh glyph. Added a circular-arrow 'refresh'
icon to UiIcon and pointed all seven Refresh buttons (Overview,
Tenants, Partners, Users, Operator team, Audit, Infrastructure) at it.

apps/operator/pages/audit.vue

@@ -209,7 +209,7 @@ function fmtRelative(iso: string | null | undefined): string {
     >
       <template #actions>
         <UiButton variant="secondary" :disabled="pending" @click="refresh()">
-          <template #leading><UiIcon name="chevDown" :size="13" /></template>
+          <template #leading><UiIcon name="refresh" :size="13" /></template>
           Refresh
         </UiButton>
       </template>