fix(dayplan): restore time-based auto-sort for places and free reorder for untimed

Timed places now auto-sort chronologically when a time is set.
Untimed places can be freely dragged between timed items.
Transports are inserted by time with per-day position override.
Fixes regression from multi-day spanning PR that removed timed/untimed split.

server/src/services/assignmentService.ts

@@ -168,6 +168,34 @@ export function getParticipants(assignmentId: string | number) {
 export function updateTime(id: string | number, placeTime: string | null, endTime: string | null) {
   db.prepare('UPDATE day_assignments SET assignment_time = ?, assignment_end_time = ? WHERE id = ?')
     .run(placeTime ?? null, endTime ?? null, id);
+
+  // Auto-sort: reorder timed assignments chronologically within the day
+  if (placeTime) {
+    const assignment = db.prepare('SELECT day_id FROM day_assignments WHERE id = ?').get(id) as { day_id: number } | undefined;
+    if (assignment) {
+      const dayAssignments = db.prepare(`
+        SELECT da.id, COALESCE(da.assignment_time, p.place_time) as effective_time
+        FROM day_assignments da
+        JOIN places p ON da.place_id = p.id
+        WHERE da.day_id = ?
+        ORDER BY da.order_index ASC
+      `).all(assignment.day_id) as { id: number; effective_time: string | null }[];
+
+      // Separate timed and untimed, sort timed by time
+      const timed = dayAssignments.filter(a => a.effective_time).sort((a, b) => {
+        const ta = a.effective_time!.includes(':') ? a.effective_time! : '99:99';
+        const tb = b.effective_time!.includes(':') ? b.effective_time! : '99:99';
+        return ta.localeCompare(tb);
+      });
+      const untimed = dayAssignments.filter(a => !a.effective_time);
+
+      // Interleave: timed in chronological order, untimed keep relative position
+      const reordered = [...timed, ...untimed];
+      const update = db.prepare('UPDATE day_assignments SET order_index = ? WHERE id = ?');
+      reordered.forEach((a, i) => update.run(i, a.id));
+    }
+  }
+
   return getAssignmentWithPlace(Number(id));
 }