fix: ignore a reload the editor has moved on from, and settle saves before resolving

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/ResourceEditor.svelte

@@ -303,10 +303,17 @@
 				labels: r.labels ?? undefined,
 				wsSpecific: r.ws_specific ?? false
 			}
-			// Dropped after the read and before the baseline below: anything an autosave queued
-			// while it was out belongs to the version being replaced, and leaving it parked would
-			// let the fresh baseline make it acceptable — sending it over the version just chosen.
-			UserDraftDbSyncer.dropPending(query)
+			// Everything below writes shared editor state, so first make sure it is still this
+			// resource's: the drawer stays closable while the read is out, and another resource
+			// opened meanwhile would otherwise get this one's baseline — and with it this one's
+			// path as its save target.
+			if (selected !== ws || initialPath !== p) return
+			// Anything an autosave queued while the read was out belongs to the version being
+			// replaced. Dropping is not enough on its own: a POST the runner already started
+			// cannot be cancelled, and if it settles after the baseline below, its rejection
+			// raises the conflict again. So wait for the chain to go quiet first.
+			await UserDraftDbSyncer.quiesce(query)
+			if (selected !== ws || initialPath !== p) return
 			UserDraftDbSyncer.clearConflict(query)
 			initialStates[ws] = structuredClone(deployedState)
 			UserDraftDbSyncer.recordRemoteSync(query, (r as any).draft_saved_at)

frontend/src/lib/components/VariableEditor.svelte

@@ -174,10 +174,17 @@
 				labels: v.labels ?? undefined,
 				wsSpecific: v.ws_specific ?? false
 			}
-			// Dropped after the read and before the baseline below: anything an autosave queued
-			// while it was out belongs to the version being replaced, and leaving it parked would
-			// let the fresh baseline make it acceptable — sending it over the version just chosen.
-			UserDraftDbSyncer.dropPending(query)
+			// Everything below writes shared editor state, so first make sure it is still this
+			// variable's: the drawer stays closable while the read is out, and another variable
+			// opened meanwhile would otherwise get this one's baseline — and with it this one's
+			// path as its save target.
+			if (selected !== ws || editPath !== p) return
+			// Anything an autosave queued while the read was out belongs to the version being
+			// replaced. Dropping is not enough on its own: a POST the runner already started
+			// cannot be cancelled, and if it settles after the baseline below, its rejection
+			// raises the conflict again. So wait for the chain to go quiet first.
+			await UserDraftDbSyncer.quiesce(query)
+			if (selected !== ws || editPath !== p) return
 			UserDraftDbSyncer.clearConflict(query)
 			initialStates[ws] = structuredClone(deployedState)
 			UserDraftDbSyncer.recordRemoteSync(query, (v as any).draft_saved_at)

frontend/src/lib/userDraftDbSyncer.svelte.ts

@@ -723,5 +723,20 @@ export const UserDraftDbSyncer = {
 		const key = draftKey(query.workspace, query.itemKind, query.path)
 		pendingSaveOpts.delete(key)
 		debouncer.cancel(key)
+	},
+
+	/**
+	 * Drop what is parked and wait until nothing for this key is still in flight. `dropPending`
+	 * alone cannot stop a POST the runner already started, and such a POST settles *after* the
+	 * caller has moved on — a rejected one re-raising the conflict it was told to resolve. Await
+	 * this before installing a baseline that would make a stale payload acceptable.
+	 */
+	async quiesce(query: UserDraftLastSyncQuery): Promise<void> {
+		const key = draftKey(query.workspace, query.itemKind, query.path)
+		this.dropPending(query)
+		await runner.settled(key)
+		// A save that landed while we waited parks its own opts again; they belong to the version
+		// being replaced, so they go too.
+		this.dropPending(query)
 	}
 }