editor: fix scrambled timeline clip order after global-prompt edits

The cut order (timeline_order) is a list of scene ids. Editing the global
prompt rebuilds the plan and reassigns scene content to ids positionally, but
_distributeGlobalPrompt left timeline_order untouched — so a stale id sequence
scrambled the live clips against their plan badges (e.g. 01,02,04,03,...),
even though ghost re-layout (plan-anchored) stayed correct.

Fix: the cut order tracks the plan until the user explicitly pins a custom
order via the ◀ ▶ arrows. New Project.timeline_manually_ordered flag, set by
moveTimelineClip; _ensureTimelineOrder follows plan order when it's unset and
heals (survivors keep their manual order, new appended) when set. Reconcile on
global-prompt apply too. Existing drifted projects self-heal on load.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

movie_editor/backend/timeline.py

@@ -597,6 +597,10 @@ class Project:
     # Cut order: scene ids in TIMELINE (result) order, independent of plan (scenes) order.
     # Empty = follow plan order (back-compat). Reordering the plan never touches this.
     timeline_order: list = field(default_factory=list)
+    # True once the user explicitly reordered a timeline clip (◀ ▶). Until then the cut order
+    # tracks the plan, so editing the global prompt re-derives it cleanly instead of letting a
+    # stale id sequence scramble the clips against the plan badges.
+    timeline_manually_ordered: bool = False
     created_at: float = field(default_factory=time.time)
     updated_at: float = field(default_factory=time.time)
 
@@ -634,6 +638,7 @@ class Project:
             scene_renders=dict(d.get("scene_renders") or {}),
             scene_ghosts=list(d.get("scene_ghosts") or []),
             timeline_order=list(d.get("timeline_order") or []),
+            timeline_manually_ordered=bool(d.get("timeline_manually_ordered", False)),
             created_at=float(d.get("created_at", time.time())),
             updated_at=float(d.get("updated_at", time.time())),
         )

movie_editor/frontend/store.js

@@ -488,6 +488,9 @@
     _applyDetectedTransitions(next, v.transitions, text);
     state.project.scenes = next;
     state.sceneGhosts = ghostsOut;
+    // The global prompt is authoritative on plan order — reconcile the cut order to it now
+    // (no-op when the user has pinned a manual order; otherwise tracks the plan).
+    _ensureTimelineOrder();
     const prevSel = state.selectedSceneId;
     const stillSel = prevSel && next.some((s) => s.id === prevSel);
     const firstId = stillSel ? prevSel : (next[0]?.id || null);
@@ -1422,6 +1425,10 @@
   function _ensureTimelineOrder() {
     const p = state.project; if (!p) return;
     const ids = (p.scenes || []).map((s) => s.id);
+    // Until the user explicitly pins a custom cut order (◀ ▶), the timeline follows the plan.
+    // This keeps an edit to the global prompt — which rebuilds the plan in its own order — from
+    // leaving a stale id sequence behind that scrambles the clips against their plan badges.
+    if (!p.timeline_manually_ordered) { p.timeline_order = ids; return; }
     const idSet = new Set(ids);
     const cur = (Array.isArray(p.timeline_order) ? p.timeline_order : []).filter((id) => idSet.has(id));
     const inCur = new Set(cur);
@@ -1450,6 +1457,9 @@
     if (i === j) return;
     _historyRecord();
     order.splice(i, 1); order.splice(j, 0, id);
+    // The user has now pinned a custom cut order — a global-prompt edit must preserve it
+    // rather than re-deriving the order from the plan.
+    p.timeline_manually_ordered = true;
     notify(); scheduleSave();
   }