chore(sync): enable tokio io-util/net for disk-streamed chunked upload (M4.1)

Needed for AsyncReadExt/AsyncSeekExt/BufReader used to stream .wav
recordings off disk in fixed-size chunks instead of buffering the
whole file in memory (T9.2 refinement, FR-SYNC-5).

src-tauri/Cargo.toml

@@ -23,7 +23,7 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 thiserror = "1"
 async-trait = "0.1"
-tokio = { version = "1", features = ["rt-multi-thread", "macros", "sync", "time", "fs"] }
+tokio = { version = "1", features = ["rt-multi-thread", "macros", "sync", "time", "fs", "io-util", "net"] }
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 uuid = { version = "1", features = ["v4"] }