Propagate waypoint notes through session init, save-to-journal, and Journal display

- use-yjs: seed note from initialWaypoints on session open
- api.sessions: include note in initialWaypoints type
- SaveToJournalButton: include note in GPX waypoints on save
- Journal routes.: map and display waypoint notes

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/planner/app/components/SaveToJournalButton.tsx

@@ -47,6 +47,7 @@ export function SaveToJournalButton({ yjs, callbackUrl, callbackToken, returnUrl
         lon: yMap.get("lon") as number,
         name: yMap.get("name") as string | undefined,
         isDayBreak: yMap.get("overnight") === true ? true : undefined,
+        note: yMap.get("note") as string | undefined,
         osmId: yMap.get("osmId") as number | undefined,
         poiTags: yMap.get("poiTags") as WaypointPoiTags | undefined,
       }));