logiguard fork v3: full patch set on verified 8c74db0 tree

Includes prior-session patches (carry forward so the app compiles):
  - crates/gpui/build.rs: cross-compile manifest fix
  - crates/gpui/src/platform.rs: PlatformWindow::activate_with_token trait method
  - crates/gpui/src/window.rs: Window::activate_with_token public API
  - crates/gpui_linux/src/linux/wayland/window.rs: WaylandWindow::activate_with_token + activate() keyboard-serial fix

Plus the focus-serial fix:
  - serial.rs: SerialKind::KeyboardEnter
  - client.rs: store wl_keyboard.enter serial; latest_serial_of()

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/env_var/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "env_var"
+version = "0.1.0"
+edition.workspace = true
+publish.workspace = true
+license = "GPL-3.0-or-later"
+
+[lints]
+workspace = true
+
+[lib]
+path = "src/env_var.rs"
+
+[dependencies]
+gpui_shared_string.workspace = true

crates/env_var/LICENSE-GPL

@@ -0,0 +1 @@
+../../LICENSE-GPL

crates/env_var/src/env_var.rs

@@ -0,0 +1,40 @@
+use gpui_shared_string::SharedString;
+
+#[derive(Clone)]
+pub struct EnvVar {
+    pub name: SharedString,
+    /// Value of the environment variable. Also `None` when set to an empty string.
+    pub value: Option<String>,
+}
+
+impl EnvVar {
+    pub fn new(name: SharedString) -> Self {
+        let value = std::env::var(name.as_str()).ok();
+        if value.as_ref().is_some_and(|v| v.is_empty()) {
+            Self { name, value: None }
+        } else {
+            Self { name, value }
+        }
+    }
+
+    pub fn or(self, other: EnvVar) -> EnvVar {
+        if self.value.is_some() { self } else { other }
+    }
+}
+
+/// Creates a `LazyLock<EnvVar>` expression for use in a `static` declaration.
+#[macro_export]
+macro_rules! env_var {
+    ($name:expr) => {
+        ::std::sync::LazyLock::new(|| $crate::EnvVar::new(($name).into()))
+    };
+}
+
+/// Generates a `LazyLock<bool>` expression for use in a `static` declaration. Checks if the
+/// environment variable exists and is non-empty.
+#[macro_export]
+macro_rules! bool_env_var {
+    ($name:expr) => {
+        ::std::sync::LazyLock::new(|| $crate::EnvVar::new(($name).into()).value.is_some())
+    };
+}