feat: Add instructions for local development and deployment

Updates README.md with clear steps for running the AI Studio app locally, including prerequisites and commands.
Introduces a .env.example file to guide users on API key configuration.
Adds a .gitignore file to prevent unnecessary files from being committed.
Updates asset files (images) with new metadata.

metadata.json

@@ -0,0 +1,5 @@
+{
+  "name": "",
+  "description": "",
+  "requestFramePermissions": []
+}