feat: add Bun polyfills and refactor LiteMCP implementation

- Introduced polyfills for Node.js compatibility in Bun runtime
- Moved LiteMCP implementation to a dedicated module
- Updated package.json to include @digital-alchemy/hass dependency
- Refactored import for LiteMCP to use local module path

src/polyfills.js

@@ -0,0 +1,9 @@
+// Add necessary polyfills for Node.js compatibility in Bun
+import { webcrypto } from 'node:crypto';
+
+// Polyfill for crypto.subtle in Bun
+if (!globalThis.crypto?.subtle) {
+    globalThis.crypto = webcrypto;
+}
+
+// Add any other necessary polyfills here