feat(desktop): implement workspace foundation + desktop-client skeleton

Plan 0 (workspaces): add workspaces + workspace_memberships schema, extend
JWT/Actor/claims with primary_workspace_id, seed default workspace per tenant,
thread workspace_id through tenant monitoring quota.

Plan A (desktop skeleton): new Electron app (apps/desktop-client) with main/
preload/renderer, shared Vue component package (packages/ui-shared), and server
surface — desktop client registration + token rotation + heartbeat, SSE task
event stream, desktop accounts/tasks/content handlers, publish job endpoint,
and supporting repositories, services, sqlc queries, and migrations.

Hard cutover per plan: remove browser-extension monitoring callback endpoints,
stub legacy media API in admin-web, and delete monitoring_callback_handler.go.

apps/desktop-client/src/renderer/components/StatusBadge.vue

@@ -0,0 +1,68 @@
+<script setup lang="ts">
+const props = defineProps<{
+  tone?: "neutral" | "brand" | "success" | "warn" | "danger" | "info";
+  label: string;
+  subtle?: boolean;
+}>();
+</script>
+
+<template>
+  <span class="badge" :class="[props.tone ?? 'neutral', { subtle: props.subtle }]">
+    {{ props.label }}
+  </span>
+</template>
+
+<style scoped>
+.badge {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 26px;
+  padding: 0 10px;
+  border-radius: 999px;
+  border: 1px solid var(--geo-color-border);
+  background: rgba(255, 255, 255, 0.42);
+  color: var(--geo-color-text-secondary);
+  font-size: 12px;
+  font-weight: 600;
+  letter-spacing: 0.02em;
+}
+
+.subtle {
+  background: transparent;
+}
+
+.brand {
+  color: var(--geo-color-brand-strong);
+  background: var(--geo-color-brand-soft);
+  border-color: rgba(15, 118, 110, 0.24);
+}
+
+.success {
+  color: var(--geo-color-success);
+  background: var(--geo-color-success-soft);
+  border-color: rgba(21, 128, 61, 0.22);
+}
+
+.warn {
+  color: var(--geo-color-warn);
+  background: var(--geo-color-warn-soft);
+  border-color: rgba(180, 83, 9, 0.22);
+}
+
+.danger {
+  color: var(--geo-color-danger);
+  background: var(--geo-color-danger-soft);
+  border-color: rgba(185, 28, 28, 0.22);
+}
+
+.info {
+  color: var(--geo-color-info);
+  background: var(--geo-color-info-soft);
+  border-color: rgba(37, 99, 235, 0.22);
+}
+
+html[data-theme="dark"] .badge {
+  background: rgba(255, 255, 255, 0.04);
+}
+</style>