Datasets: URL→inline conversion drops url/fetchedAt

src/app/stores/DatasetStore.ts

@@ -291,11 +291,9 @@ export const useDatasetStore = create<DatasetState>((set, get) => ({
           data: resolved.data,
           format: resolved.format,
           source: resolved.source,
-          // TODO: `update` shallow-merges, so these set the keys to `undefined`
-          // rather than removing them — a URL→inline record keeps `url`/`fetchedAt`
-          // present-but-undefined. Invisible today (rendering/profiling key off
-          // `source`/`data == null`, and JSON export drops undefined), but it breaks
-          // the "inline records carry no url/fetchedAt keys" invariant on this path.
+          // A URL→inline conversion must shed the remote origin; `update` deletes
+          // keys set to `undefined`, so these are removed rather than left
+          // present-but-undefined.
           url: undefined,
           fetchedAt: undefined,
           comment: form.comment,
@@ -415,7 +413,18 @@ export const useDatasetStore = create<DatasetState>((set, get) => ({
   update: (id, patch, now) => {
     const modified = patch.modified ?? (now ?? new Date()).toISOString();
     set((s) => ({
-      datasets: s.datasets.map((d) => (d.id === id ? { ...d, ...patch, modified } : d)),
+      datasets: s.datasets.map((d) => {
+        if (d.id !== id) return d;
+        const merged = { ...d, ...patch, modified };
+        // A patch key set to `undefined` removes it, rather than leaving a
+        // present-but-undefined key — so a URL→inline conversion drops `url`/
+        // `fetchedAt` cleanly, keeping the "inline records carry no remote-origin
+        // keys" invariant (docs/architecture/07 §6).
+        for (const key of Object.keys(patch) as (keyof Dataset)[]) {
+          if (patch[key] === undefined) delete merged[key];
+        }
+        return merged;
+      }),
     }));
   },