Deprecated top-level library fields removed from batch payloads

1.35.2

Patch Changes

• #3886 e6d7fe2 Thanks @marandaneto! - Stop sending deprecated no-op top-level type, library, and library_version fields in event batch payloads. Use properties.$lib and properties.$lib_version for SDK metadata; legacy queued library and library_version values are used as fallbacks when the official $ properties are missing. (2026-06-18)