chore(vendor): import pi 0.85.1

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

third_party/pi/packages/ai/src/models-store.ts

@@ -0,0 +1,45 @@
+import type { Api, Model } from "./types.ts";
+
+export interface ModelsStoreEntry {
+	models: readonly Model<Api>[];
+	/** Unix timestamp from the remote catalog's Last-Modified header. */
+	lastModified?: number;
+	/** Unix timestamp of the last completed remote check. */
+	checkedAt?: number;
+	/**
+	 * Opaque validator from the remote catalog's ETag header, stored verbatim
+	 * (quotes included) and echoed back as If-None-Match.
+	 */
+	etag?: string;
+}
+
+export interface ModelsStoreOperationOptions {
+	signal?: AbortSignal;
+}
+
+/** Persistent model catalogs keyed by provider ID. */
+export interface ModelsStore {
+	read(providerId: string, options?: ModelsStoreOperationOptions): Promise<ModelsStoreEntry | undefined>;
+	write(providerId: string, entry: ModelsStoreEntry, options?: ModelsStoreOperationOptions): Promise<void>;
+	delete(providerId: string, options?: ModelsStoreOperationOptions): Promise<void>;
+}
+
+export class InMemoryModelsStore implements ModelsStore {
+	private readonly entries = new Map<string, ModelsStoreEntry>();
+
+	async read(providerId: string, options?: ModelsStoreOperationOptions): Promise<ModelsStoreEntry | undefined> {
+		options?.signal?.throwIfAborted();
+		const entry = this.entries.get(providerId);
+		return entry ? structuredClone(entry) : undefined;
+	}
+
+	async write(providerId: string, entry: ModelsStoreEntry, options?: ModelsStoreOperationOptions): Promise<void> {
+		options?.signal?.throwIfAborted();
+		this.entries.set(providerId, structuredClone(entry));
+	}
+
+	async delete(providerId: string, options?: ModelsStoreOperationOptions): Promise<void> {
+		options?.signal?.throwIfAborted();
+		this.entries.delete(providerId);
+	}
+}