Metadata: Allow setting pro metadata in OSS

It's common for folks to use both OSS and PRO/Cloud versions of hasura in a single workflow.

For example, a locally hosted OSS instance may be used for development, and the metadata is then deployed to Cloud.

### Is your proposal related to a problem?

Currently, some metadata can only be set in the PRO/Cloud version of the console.

Specifically, metadata pertaining to PRO/Cloud exclusive features: API limits, read replicas, etc.

This can lead to users accidentally overwriting this PRO/Cloud exclusive metadata when deploying new metadata from the dev environment.

### Describe the solution you'd like

Users should be able to configure PRO/Cloud exclusive metadata in their dev environment that runs OSS.

### Describe alternatives you've considered

Users can manually overcome this UI shortcoming by either writing metadata manually or exporting metadata from a PRO/Cloud environment into source control. This is awkward and requires familiarity with metadata and how it works.

The issue mentions the OSS/PRO/Cloud console and metadata for API limits and read replicas, but names no files or tests. Begin by locating the console's metadata configuration and deployment paths; done means OSS can configure and retain PRO/Cloud-exclusive metadata so deploying from development does not overwrite it.

Written by the indexing model from the issue text.