chore: clean Rust warnings and remove unused deps

- Remove serde_yaml and tokio from Cargo.toml (unused)
- Add #[allow(dead_code)] to utility code kept for future use
  (CUT_FULL, ALIGN_RIGHT, line(), PrinterError, SupabaseError,
   atualizar_sync, remover, Lock variant)
- Zero compiler warnings on release build

src-tauri/Cargo.toml

@@ -15,8 +15,6 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 rusqlite = { version = "0.32", features = ["bundled"] }
 reqwest = { version = "0.12", features = ["json", "blocking"] }
-tokio = { version = "1", features = ["full"] }
-serde_yaml = "0.9"
 uuid = { version = "1", features = ["v4"] }
 chrono = { version = "0.4", features = ["serde"] }
 log = "0.4"