fix: make canvas node sync idempotent

lib/db/queries.ts

@@ -11,6 +11,7 @@ import {
   inArray,
   like,
   lt,
+  notInArray,
   or,
   sql,
   type SQL,
@@ -1711,7 +1712,6 @@ export async function syncCanvasNodesForProject(params: {
       eq(mediaAssetRelation.relationType, "located_on_canvas"),
     ),
   );
-  await db.delete(canvasNode).where(eq(canvasNode.projectId, params.projectId));
 
   const now = new Date();
   const insertableNodes = enrichedNodes.map((node) => {
@@ -1744,7 +1744,32 @@ export async function syncCanvasNodesForProject(params: {
   });
 
   if (insertableNodes.length > 0) {
-    await db.insert(canvasNode).values(insertableNodes);
+    await db
+      .insert(canvasNode)
+      .values(insertableNodes)
+      .onConflictDoUpdate({
+        target: canvasNode.id,
+        set: {
+          projectId: sql`excluded."projectId"`,
+          type: sql`excluded."type"`,
+          position: sql`excluded."position"`,
+          size: sql`excluded."size"`,
+          data: sql`excluded."data"`,
+          connections: sql`excluded."connections"`,
+          parentId: sql`excluded."parentId"`,
+          updatedAt: sql`excluded."updatedAt"`,
+        },
+      });
+
+    const activeNodeIds = insertableNodes.map((node) => node.id);
+    await db.delete(canvasNode).where(
+      and(
+        eq(canvasNode.projectId, params.projectId),
+        notInArray(canvasNode.id, activeNodeIds),
+      ),
+    );
+  } else {
+    await db.delete(canvasNode).where(eq(canvasNode.projectId, params.projectId));
   }
 
   for (const node of enrichedNodes) {