feat: track recently visited flows for command palette empty state

Calls addRecentFlow after tree data loads in both TreeNavigationPage and
ProceduralNavigationPage so the command palette can surface recent flows
when the query is empty.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/ProceduralNavigationPage.tsx

@@ -29,6 +29,7 @@ import { TicketPickerModal } from '@/components/session/TicketPickerModal'
 import { TicketLinkIndicator } from '@/components/session/TicketLinkIndicator'
 import { UpdateTicketModal } from '@/components/session/UpdateTicketModal'
 import type { PSATicketInfo } from '@/types/integrations'
+import { addRecentFlow } from '@/lib/recentFlows'
 
 interface StepState {
   notes: string
@@ -213,6 +214,7 @@ export function ProceduralNavigationPage() {
         return
       }
       setTree(treeData)
+      addRecentFlow({ id: treeData.id, name: treeData.name, tree_type: treeData.tree_type })
 
       // If resuming an existing session
       if (locationState?.sessionId) {

frontend/src/pages/TreeNavigationPage.tsx

@@ -27,6 +27,7 @@ import { TicketPickerModal } from '@/components/session/TicketPickerModal'
 import { TicketLinkIndicator } from '@/components/session/TicketLinkIndicator'
 import { UpdateTicketModal } from '@/components/session/UpdateTicketModal'
 import type { PSATicketInfo } from '@/types/integrations'
+import { addRecentFlow } from '@/lib/recentFlows'
 
 interface LocationState {
   sessionId?: string
@@ -325,6 +326,7 @@ export function TreeNavigationPage() {
       }
 
       setTree(treeData)
+      addRecentFlow({ id: treeData.id, name: treeData.name, tree_type: treeData.tree_type })
 
       // If resuming a session
       if (locationState?.sessionId) {