Update Subgraph Radio configs

[neriumrevolta]

• [x] Added Grafana dashboard JSON for Subgraph Radio
• [x] Swapped POI Radio with Subgraph Radio
• [x] Added SubgraphRadioGraphQL datasource config
• [x] Prometheus container now scrapes Subgraph Radio metrics
• [x] Add sensible defaults + options to override them for Subgraph Radio
• [x] Improved docs a bit

[trader-payne]

@axiomatic-aardvark shoot I missed merging this before updating, can you resolve the conflicts or kill the PR and redo it please? 🙏🏻

[neriumrevolta]

@axiomatic-aardvark shoot I missed merging this before updating, can you resolve the conflicts or kill the PR and redo it please? 🙏🏻

will redo 🙌🏻