move pi-mono into companion-cloud as apps/companion-os

- Copy all pi-mono source into apps/companion-os/
- Update Dockerfile to COPY pre-built binary instead of downloading from GitHub Releases
- Update deploy-staging.yml to build pi from source (bun compile) before Docker build
- Add apps/companion-os/** to path triggers
- No more cross-repo dispatch needed

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/web-ui/src/storage/store.ts

@@ -0,0 +1,33 @@
+import type { StorageBackend, StoreConfig } from "./types.js";
+
+/**
+ * Base class for all storage stores.
+ * Each store defines its IndexedDB schema and provides domain-specific methods.
+ */
+export abstract class Store {
+  private backend: StorageBackend | null = null;
+
+  /**
+   * Returns the IndexedDB configuration for this store.
+   * Defines store name, key path, and indices.
+   */
+  abstract getConfig(): StoreConfig;
+
+  /**
+   * Sets the storage backend. Called by AppStorage after backend creation.
+   */
+  setBackend(backend: StorageBackend): void {
+    this.backend = backend;
+  }
+
+  /**
+   * Gets the storage backend. Throws if backend not set.
+   * Concrete stores must use this to access the backend.
+   */
+  protected getBackend(): StorageBackend {
+    if (!this.backend) {
+      throw new Error(`Backend not set on ${this.constructor.name}`);
+    }
+    return this.backend;
+  }
+}