Refactor to Cargo Workspace (#129)

* Refactor project into a Cargo workspace with distinct packages

- Created a root `Cargo.toml` defining a workspace.
- Moved `src/types` and `src/utils` into a new `pwsp-lib` crate for shared logic.
- Split binaries into their own crates: `pwsp-daemon`, `pwsp-cli`, and `pwsp-gui`.
- Shifted all dependencies into `[workspace.dependencies]` for centralized version management.
- Updated import paths across all crates (e.g. from `pwsp::` to `pwsp_lib::`).
- Updated build scripts, GitHub actions, Flatpak manifest, and AUR PKGBUILD to support the new workspace structure.
- Ensured no core application logic was altered.

Co-authored-by: arabianq <55220741+arabianq@users.noreply.github.com>

* Fix cargo-deb build process in GitHub actions for workspace architecture

Co-authored-by: arabianq <55220741+arabianq@users.noreply.github.com>

* Fix cargo-deb asset discovery by using exact target/release paths

Co-authored-by: arabianq <55220741+arabianq@users.noreply.github.com>

* refactor deps in Cargo.toml files

* fix incorrect assets path

---------

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>

pwsp-gui/src/main.rs

@@ -0,0 +1,60 @@
+mod gui;
+
+use anyhow::{Context, Result};
+use pwsp_lib::utils::gui::ensure_pwsp_audio_dir;
+use rust_i18n::i18n;
+use std::{env, path::PathBuf};
+
+i18n!("locales", fallback = "en");
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    let locale = sys_locale::get_locale().unwrap_or(String::from("en-US"));
+    rust_i18n::set_locale(&locale);
+
+    let args = env::args().skip(1).collect::<Vec<String>>();
+
+    if let Some(uri) = args.first() {
+        match download_audio_from_url(uri).await {
+            Ok(path) => println!("Successfully downloaded to: {:?}", path),
+            Err(e) => eprintln!("Error downloading file: {}", e),
+        }
+    } else {
+        gui::run().await?;
+    }
+
+    Ok(())
+}
+
+async fn download_audio_from_url(uri: &str) -> Result<PathBuf> {
+    let prefix = "soundpad://sound/url/";
+
+    let target_url = uri
+        .strip_prefix(prefix)
+        .ok_or_else(|| anyhow::anyhow!("URI does not containt an expected prefix: {}", prefix))?;
+
+    let file_name_encoded = target_url
+        .split('/')
+        .next_back()
+        .unwrap_or("downloaded_audio.mp3");
+
+    let file_name = percent_encoding::percent_decode_str(file_name_encoded)
+        .decode_utf8()
+        .unwrap_or_else(|_| file_name_encoded.into())
+        .into_owned();
+
+    let save_path = ensure_pwsp_audio_dir().join(file_name);
+
+    let response = reqwest::get(target_url)
+        .await?
+        .error_for_status()
+        .context("Failed to fetch file")?;
+
+    let bytes = response.bytes().await?;
+
+    tokio::fs::write(&save_path, bytes)
+        .await
+        .context("Failed to save file to disk")?;
+
+    Ok(save_path)
+}