Support default instance variables for automatic project loading

[jturbide]

Description
Requesting support for configuring default instance-level variables such as a default server URL, default project hash, and a secret/token. When provided, these values would allow an instance to automatically load and initialize a project without requiring manual setup through the UI.

Intended behavior:
• Define default server URL at startup.
• Define a default project identifier (hash or slug).
• Optionally provide a secret or access token for authenticated access.
• Automatically bootstrap the instance using these values on load.

This would enable preconfigured deployments, embedded instances, demos, and controlled environments where manual configuration is unnecessary or undesirable.