### What does this PR do?
- removes the `Unimplemented in Bun` comment on `CompressionStream` and
`DecompressionStream`
- updates the types for `CompressionStream` and `DecompressionStream` to
add a new internal `CompressionFormat` type to the constructor, which
adds `brotli` and `zstd` to the union
- adds tests for brotli and zstd usage
- adds lib.dom.d.ts exclusions for brotli and zstd as these don't exist
in the DOM version of CompressionFormat
fixes#25367
### How did you verify your code works?
typechecks and tests
