fix: gate tauri-winrt-notification behind cfg(windows)

The crate was listed in general [dependencies] instead of
[target.'cfg(windows)'.dependencies], causing macOS and Linux CI
builds to compile its windows-future dependency chain and fail with
"cannot find type IMarshal in module windows_core::imp". The Windows
build passed because the types exist there.

The source code was already correctly gated — notifications.rs uses
#[cfg(target_os = "windows")] around the Toast import — so only the
Cargo.toml manifest needed the fix.

Author: proofofprints

src-tauri/Cargo.toml

@@ -36,14 +36,14 @@ tauri-plugin-dialog = "2"
 tauri-plugin-fs = "2"
 tauri-plugin-notification = "2"
 tauri-plugin-updater = "2"
-tauri-winrt-notification = "0.7"
 axum = "0.7"
 tower = "0.5"
 tower-http = { version = "0.6", features = ["cors"] }
 uuid = { version = "1", features = ["v4"] }
 
 [target.'cfg(windows)'.dependencies]
 windows-sys = { version = "0.61", features = ["Win32_Foundation", "Win32_System_Registry", "Win32_Security"] }
+tauri-winrt-notification = "0.7"
 
 [profile.release]
 panic = "abort"