fix: curate swap endpoint name, reorder date field, 404 on missing asset

- Rename /curate/retag to /curate/swap; response now includes new_tag
- /curate/reorder: read body["order"] key (was ordered_ids); include date field
- /curate/remove and /curate/swap: return 404 if asset_id not found
- Update phase3.html JS fetch calls and reorder payload to match spec

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

services/travel-memories/app/routes/curate.py

@@ -28,31 +28,31 @@ def curate():
 def remove():
     body = request.get_json()
     state = load_state(body["album_id"], current_app)
-    for p in state.photos:
-        if p.id == body["asset_id"]:
-            p.tag = "skip"
-            break
+    photo = next((p for p in state.photos if p.id == body["asset_id"]), None)
+    if photo is None:
+        return jsonify({"ok": False, "error": "photo not found"}), 404
+    photo.tag = "skip"
     save_state(state, current_app)
     return jsonify({"ok": True})
 
 
-@bp.post("/curate/retag")
-def retag():
+@bp.post("/curate/swap")
+def swap():
     body = request.get_json()
     state = load_state(body["album_id"], current_app)
-    for p in state.photos:
-        if p.id == body["asset_id"]:
-            p.tag = "story" if p.tag == "journal" else "journal"
-            break
+    photo = next((p for p in state.photos if p.id == body["asset_id"]), None)
+    if photo is None:
+        return jsonify({"ok": False, "error": "photo not found"}), 404
+    photo.tag = "story" if photo.tag == "journal" else "journal"
     save_state(state, current_app)
-    return jsonify({"ok": True})
+    return jsonify({"ok": True, "new_tag": photo.tag})
 
 
 @bp.post("/curate/reorder")
 def reorder():
     body = request.get_json()
     state = load_state(body["album_id"], current_app)
-    order_map = {aid: i for i, aid in enumerate(body["ordered_ids"])}
+    order_map = {aid: i for i, aid in enumerate(body["order"])}
     for p in state.photos:
         if p.id in order_map:
             p.order = order_map[p.id]