sdk/internal/x: generate `x` package from `x` component template

Idea from https://github.com/open-telemetry/opentelemetry-go/pull/7361

- Ref: https://github.com/open-telemetry/opentelemetry-go/pull/7361
- Components that need to be processed: [sdk/internal/x](https://github.com/open-telemetry/opentelemetry-go/blob/982391315f5559de2a3854b9fd45fe91d99f67a4/sdk/internal/x)