Add dataset library, extract-to-dataset, and render-time reference resolution

src/app/infrastructure/dataset-migrations.ts

@@ -0,0 +1,51 @@
+/**
+ * Read-time migration for Dataset records (docs/architecture/02 §4, spec §09B).
+ *
+ * Mirrors snippet-migrations: every dataset read from storage passes through
+ * `migrateDataset`, which fills missing/old fields and stamps the current
+ * version. It tolerates unknown fields (spread the original, only fill gaps) so a
+ * record written by a newer build round-trips without data loss. Records written
+ * before versioning existed (no `version`) are treated as v1.
+ */
+
+import { CURRENT_DATASET_VERSION, type DataSource, type Dataset } from '@core/dataset';
+import type { DataFormat } from '@core/format-detection';
+import type { ColumnType } from '@core/type-inference';
+
+const FORMATS: ReadonlyArray<DataFormat> = ['json', 'csv', 'tsv', 'topojson'];
+
+function asFormat(v: unknown): DataFormat {
+  return typeof v === 'string' && (FORMATS as string[]).includes(v) ? (v as DataFormat) : 'json';
+}
+
+function asSource(v: unknown): DataSource {
+  return v === 'url' ? 'url' : 'inline';
+}
+
+function asCount(v: unknown): number | null {
+  return typeof v === 'number' && Number.isFinite(v) ? v : null;
+}
+
+/** Upgrade a raw stored record to the current Dataset shape. */
+export function migrateDataset(raw: unknown): Dataset {
+  const r = { ...(raw as Record<string, unknown>) };
+  return {
+    ...r,
+    id: typeof r.id === 'number' ? r.id : Number(r.id),
+    version: CURRENT_DATASET_VERSION,
+    name: typeof r.name === 'string' ? r.name : 'Untitled',
+    data: r.data,
+    format: asFormat(r.format),
+    source: asSource(r.source),
+    comment: typeof r.comment === 'string' ? r.comment : '',
+    rowCount: asCount(r.rowCount),
+    columnCount: asCount(r.columnCount),
+    columns: Array.isArray(r.columns) ? (r.columns as string[]) : [],
+    columnTypes: Array.isArray(r.columnTypes)
+      ? (r.columnTypes as Array<{ name: string; type: ColumnType }>)
+      : [],
+    size: typeof r.size === 'number' ? r.size : 0,
+    created: typeof r.created === 'string' ? r.created : new Date(0).toISOString(),
+    modified: typeof r.modified === 'string' ? r.modified : new Date(0).toISOString(),
+  };
+}

src/app/infrastructure/dataset-store.ts

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+/**
+ * Dataset persistence adapter (docs/architecture/02, spec §09E).
+ *
+ * The typed seam between the dataset store and IndexedDB's high-capacity
+ * `datasets` object store (separate from snippets so large payloads live in a
+ * tier suited to them). Exposes plain async functions returning domain `Dataset`
+ * objects and migrates every record on read.
+ */
+
+import { CURRENT_DATASET_VERSION, type Dataset } from '@core/dataset';
+import { DATASETS_STORE, del, getAll, put } from './db';
+import { migrateDataset } from './dataset-migrations';
+
+/** Load every dataset, upgrading each record to the current shape. */
+export async function loadDatasets(): Promise<Dataset[]> {
+  const records = await getAll<unknown>(DATASETS_STORE);
+  return records.map(migrateDataset);
+}
+
+/** Persist a dataset at the current schema version. Propagates failures. */
+export async function saveDataset(dataset: Dataset): Promise<void> {
+  await put(DATASETS_STORE, { ...dataset, version: CURRENT_DATASET_VERSION });
+}
+
+/** Permanently remove a dataset by id. */
+export async function deleteDataset(id: number): Promise<void> {
+  await del(DATASETS_STORE, id);
+}