feat(operator): command palette, impersonation, incident, tweaks (O.8)

- CommandPalette + useCommandPalette: ⌘K opens a search-and-jump panel over
  real tenants/partners + fixture flags + nav + actions. Arrow keys + Enter
  navigate, Escape/backdrop close. Recents are intentionally omitted for now;
  add when there's something to recent over.
- Impersonation stub: useImpersonation + ImpersonationModal + ImpersonationBanner.
  Modal opens from tenant detail and from the palette. Banner stays at the top
  of the shell until exited. No real OBO token is minted — wiring OAuth Token
  Exchange is tracked as a follow-up.
- IncidentModal + useIncidentModal: opened from the Overview and Infrastructure
  incident banners, renders the mock INCIDENT data with metrics, timeline and
  draft composer.
- TweaksPanel + useTweaks: floating bottom-right panel for theme (dark/light),
  density (comfy/compact), env badge (prod/staging/dev). Saved to localStorage.
- Theme/density apply via [data-theme] + [data-density] overrides in
  tokens.css. Topbar env badge now reads from useTweaks instead of a prop.
- Layout wires ⌘K + ⌘[ at the document level and mounts the palette + modals
  + banner + tweaks panel once for all pages.

apps/operator/pages/index.vue

@@ -8,6 +8,8 @@ const { data: tenants, pending: tp, refresh: rT } = await useFetch<Tenant[]>('/a
 const { data: partners, pending: pp, refresh: rP } = await useFetch<Partner[]>('/api/partners', { default: () => [] })
 const { data: users, pending: up, refresh: rU } = await useFetch<PlatformUser[]>('/api/users', { default: () => [] })
 
+const { open: openIncident } = useIncidentModal()
+
 const pending = computed(() => tp.value || pp.value || up.value)
 
 async function refresh() {
@@ -63,7 +65,7 @@ function fmtDate(d: string) {
     </PageHeader>
 
     <div class="stage">
-      <button v-if="incidentActive" class="incident" type="button">
+      <button v-if="incidentActive" class="incident" type="button" @click="openIncident">
         <span class="pill">
           <span class="dot" />
           {{ INCIDENT.severity }} · ACTIVE

apps/operator/pages/infrastructure.vue

@@ -3,6 +3,7 @@ import { SERVICES, INCIDENT, type PlatformService } from '~/data/fixtures'
 
 const degradedCount = computed(() => SERVICES.filter((s) => s.status !== 'ok').length)
 const incidentActive = computed(() => degradedCount.value > 0)
+const { open: openIncident } = useIncidentModal()
 
 function tone(s: PlatformService): 'ok' | 'warn' | 'bad' {
   return s.status
@@ -41,7 +42,7 @@ function label(s: PlatformService) {
           <div class="title">{{ INCIDENT.title }}</div>
           <div class="sub">Started {{ INCIDENT.started }} · IC: {{ INCIDENT.ic }}</div>
         </div>
-        <UiButton variant="primary" disabled>Open incident</UiButton>
+        <UiButton variant="primary" @click="openIncident">Open incident</UiButton>
       </div>
 
       <div class="grid">

apps/operator/pages/tenants/[slug].vue

@@ -10,6 +10,8 @@ const { data: tenant, refresh: refreshTenant } = await useFetch<Tenant>(() => `/
 
 const activeTab = ref<'overview' | 'users' | 'resources' | 'billing' | 'audit' | 'support' | 'danger'>('overview')
 
+const impersonate = useImpersonation()
+
 // Lazy-fetch users only when the tab is opened.
 const { data: users, refresh: refreshUsers } = useLazyFetch<TenantUser[]>(
   () => `/api/tenants/${slug.value}/users`,
@@ -97,6 +99,10 @@ async function reconcile() {
       <template #actions>
         <Badge :tone="STATUS_TONE[tenant.status]" dot>{{ tenant.status }}</Badge>
         <Badge tone="neutral">{{ tenant.plan }}</Badge>
+        <UiButton variant="secondary" @click="impersonate.open(tenant)">
+          <template #leading><UiIcon name="key" :size="13" /></template>
+          Impersonate
+        </UiButton>
         <UiButton variant="secondary">
           <template #leading><UiIcon name="external" :size="13" /></template>
           Open workspace