web/storage: add memory storage and init() function

web/src/lib/storage/index.ts

@@ -0,0 +1,15 @@
+import type { AbstractStorage } from "./storage";
+import { MemoryStorage } from "./memory";
+import { OPFSStorage } from "./opfs";
+
+export function init(expectedSize?: number): Promise<AbstractStorage> {
+    if (OPFSStorage.isAvailable()) {
+        return OPFSStorage.init();
+    }
+
+    if (MemoryStorage.isAvailable()) {
+        return MemoryStorage.init(expectedSize || 0);
+    }
+
+    throw "no storage method is available";
+}