Currently, three of the OpenTelemetry settings -- otel-endpoint, otel-env-vars, and otel-sampling-rate -- can be configured "globally", set in the ToolHive config file using thv config otel ... and used across all MCP servers.

There are two (maybe three) other settings on the thv run command that would be nice to complete this coverage: otel-insecure, and otel-enable-prometheus-metrics-path are simple booleans.

The third, otel-headers, is debatable as it's typically going to be an API key - so it leads into needing secrets handling to populate it, so we could leave it out for now and users can continue set it on the CLI using env vars.