Add initial Wayland shell with clock and system tray

- Layer-shell bars drawn in software with tiny-skia and fontdue
- Clock widget centered at the top of the screen
- System tray in a top-right notch, acting as the
  StatusNotifierWatcher, with icons and right-click menus
- Live-reloaded TOML config for colors
  (~/.config/pell/config.toml)
- devenv setup for the Rust toolchain and Wayland libraries
- README: config, tray behaviour and AI disclosure

Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "Pell"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+chrono = { version = "0.4.45", default-features = false, features = ["clock"] }
+dbus = "0.9.12"
+fontdue = "0.9.4"
+png = "0.18.1"
+serde = { version = "1.0.229", features = ["derive"] }
+smithay-client-toolkit = "0.21.1"
+tiny-skia = "0.12.0"
+toml = { version = "1.1.8", default-features = false, features = ["parse", "serde"] }