fix: title bar buttons work with a finger on Wayland (Issue #36)

winit 0.29 draws the title bar itself on Wayland but only handles the
mouse there. A vendored copy of winit 0.29.15 (vendor/winit, used via
[patch.crates-io]) passes touches on the decorations to the frame like a
left click, so close, minimize and maximize work with a finger and
dragging the title bar moves the window.

CI no longer sets a global -D warnings, which would also apply to the
vendored crate; clippy still runs with -D warnings.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

vendor/winit/src/platform/startup_notify.rs

@@ -0,0 +1,99 @@
+//! Window startup notification to handle window raising.
+//!
+//! The [`ActivationToken`] is essential to ensure that your newly
+//! created window will obtain the focus, otherwise the user could
+//! be requered to click on the window.
+//!
+//! Such token is usually delivered via the environment variable and
+//! could be read from it with the [`EventLoopExtStartupNotify::read_token_from_env`].
+//!
+//! Such token must also be reset after reading it from your environment with
+//! [`reset_activation_token_env`] otherwise child processes could inherit it.
+//!
+//! When starting a new child process with a newly obtained [`ActivationToken`] from
+//! [`WindowExtStartupNotify::request_activation_token`] the [`set_activation_token_env`]
+//! must be used to propagate it to the child
+//!
+//! To ensure the delivery of such token by other processes to you, the user should
+//! set `StartupNotify=true` inside the `.desktop` file of their application.
+//!
+//! The specification could be found [`here`].
+//!
+//! [`here`]: https://specifications.freedesktop.org/startup-notification-spec/startup-notification-latest.txt
+
+use std::env;
+
+use crate::error::NotSupportedError;
+use crate::event_loop::{AsyncRequestSerial, EventLoopWindowTarget};
+use crate::window::{ActivationToken, Window, WindowBuilder};
+
+/// The variable which is used mostly on X11.
+const X11_VAR: &str = "DESKTOP_STARTUP_ID";
+
+/// The variable which is used mostly on Wayland.
+const WAYLAND_VAR: &str = "XDG_ACTIVATION_TOKEN";
+
+pub trait EventLoopExtStartupNotify {
+    /// Read the token from the environment.
+    ///
+    /// It's recommended **to unset** this environment variable for child processes.
+    fn read_token_from_env(&self) -> Option<ActivationToken>;
+}
+
+pub trait WindowExtStartupNotify {
+    /// Request a new activation token.
+    ///
+    /// The token will be delivered inside
+    fn request_activation_token(&self) -> Result<AsyncRequestSerial, NotSupportedError>;
+}
+
+pub trait WindowBuilderExtStartupNotify {
+    /// Use this [`ActivationToken`] during window creation.
+    ///
+    /// Not using such a token upon a window could make your window not gaining
+    /// focus until the user clicks on the window.
+    fn with_activation_token(self, token: ActivationToken) -> Self;
+}
+
+impl<T> EventLoopExtStartupNotify for EventLoopWindowTarget<T> {
+    fn read_token_from_env(&self) -> Option<ActivationToken> {
+        match self.p {
+            #[cfg(wayland_platform)]
+            crate::platform_impl::EventLoopWindowTarget::Wayland(_) => env::var(WAYLAND_VAR),
+            #[cfg(x11_platform)]
+            crate::platform_impl::EventLoopWindowTarget::X(_) => env::var(X11_VAR),
+        }
+        .ok()
+        .map(ActivationToken::_new)
+    }
+}
+
+impl WindowExtStartupNotify for Window {
+    fn request_activation_token(&self) -> Result<AsyncRequestSerial, NotSupportedError> {
+        self.window.request_activation_token()
+    }
+}
+
+impl WindowBuilderExtStartupNotify for WindowBuilder {
+    fn with_activation_token(mut self, token: ActivationToken) -> Self {
+        self.platform_specific.activation_token = Some(token);
+        self
+    }
+}
+
+/// Remove the activation environment variables from the current process.
+///
+/// This is wise to do before running child processes,
+/// which may not to support the activation token.
+pub fn reset_activation_token_env() {
+    env::remove_var(X11_VAR);
+    env::remove_var(WAYLAND_VAR);
+}
+
+/// Set environment variables responsible for activation token.
+///
+/// This could be used before running daemon processes.
+pub fn set_activation_token_env(token: ActivationToken) {
+    env::set_var(X11_VAR, &token._token);
+    env::set_var(WAYLAND_VAR, token._token);
+}