declarative config: map enabled and common-enabled

See https://github.com/open-telemetry/opentelemetry-java-instrumentation/pull/14184#discussion_r2268171934

Also see https://docs.google.com/document/d/1D7ZD93LxSWexHeztHohRp5yeoTzsi9Dj1HRm7Tad-hM/edit?pli=1&tab=t.0

