Add support for compressed QMDL

Major changes:
* QmdlWriter now outputs gzipped QMDL files by default
* QmdlReader renamed to QmdlMessageReader, and reads both compressed and
  uncompressed QMDL. It no longer requires bounding to avoid reading
  partially written files.

lib/Cargo.toml

@@ -30,6 +30,7 @@ serde = { version = "1.0.197", features = ["derive"] }
 serde_json = "1.0"
 num_enum = "0.7.4"
 utoipa = { version = "5.4.0", optional = true }
+async-compression = { version = "0.4.41", features = ["tokio", "gzip"] }
 
 [dev-dependencies]
 tempfile = "3"