feat(ui-flow): digest schedule and worker install plan IPC (Phase 100)

Wire set-digest-export-schedule, run-digest-export-now, and
get-worker-install-plan sidecar messages.

Co-authored-by: Cursor <[email protected]>

index.js

@@ -154,6 +154,22 @@ async function dispatchUiMessage (platform, msg, hooks = {}) {
     send({ type: 'audit-export-scheduled', result: out })
     return true
   }
+  if (t === 'set-digest-export-schedule') {
+    await platform.setDigestExportSchedule(msg.schedule || {})
+    pushState()
+    return true
+  }
+  if (t === 'run-digest-export-now') {
+    const digest = await platform.runScheduledDigestExportNow()
+    pushState()
+    send({ type: 'digest-export-scheduled', digest })
+    return true
+  }
+  if (t === 'get-worker-install-plan') {
+    const plan = await platform.fetchWorkerInstallPlan(msg.templateId || 'message-logger')
+    send({ type: 'worker-install-plan', plan })
+    return true
+  }
   if (t === 'export-integration-worker-script') {
     const script = platform.buildIntegrationWorkerScript(msg.templateId || 'message-logger')
     send({