Remove `@opentelemetry/core` dependency

[nicohrubec]

Vendor the remaining @opentelemetry/core APIs so we can drop the dependency, tracked in the subtickets below:

• Remove @opentelemetry/core RPC metadata APIs #22280
• Remove W3CBaggagePropagator from @opentelemetry/core #22281
• Remove suppressTracing / isTracingSuppressed #22282

Once the subtickets are done, ensure the @opentelemetry/core dependency is removed everywhere (dependencies + peerDependencies in packages/opentelemetry and packages/node-core).

[linear-code]

JS-2818