Add model list configuration collector

[ronenkat]

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR introduces a new polling collector plugin modelconfigcollector that reads model configurations from a JSON file and registers them in the datastore. The collector:

• Implements the Collector interface from the data layer framework
• Reads a JSON configuration file containing a list of model names
• Periodically polls the configuration file and updates the datastore with model entries using the GetOrCreateModel interface
• Registers the plugin in the runner's in-tree plugin registry

This enables dynamic model configuration management through file-based configuration, allowing models to be added or updated without code changes.

Which issue(s) this PR fixes:

Fixes #