refactor(download manager): Fully separate & generic download manager

Signed-off-by: quexeky <git@quexeky.dev>

desktop/src-tauri/Cargo.toml

@@ -26,7 +26,6 @@ tauri-build = { version = "2.0.0", features = [] }
 
 [dependencies]
 tauri-plugin-shell = "2.0.0"
-serde = { version = "1", features = ["derive", "rc"] }
 serde_json = "1"
 serde-binary = "0.5.0"
 rayon = "1.10.0"
@@ -84,6 +83,10 @@ features = [] # You can also use "yaml_enc" or "bin_enc"
 version = "0.12"
 features = ["json", "blocking"]
 
+[dependencies.serde]
+version = "1"
+features = ["derive", "rc"]
+
 [profile.release]
 lto = true
 codegen-units = 1