Accumulate config engine, build metadata, and doc updates

Remaining files from the backlog: Lua config engine
additions (general/register/support/window), workspace Cargo.toml/
Cargo.lock churn from the new dependencies added elsewhere in this
sweep, srdwm/main.rs wiring, and docs (DEFAULTS.md plus a new
SESSION_HANDOFF.md written mid-session for continuity across a restart
- see that file's own header for what it is and isn't).

4 files changed, 37 insertions, 1 deletions

diff --git a/crates/config/src/engine/general.rs b/crates/config/src/engine/general.rs
index 96ea4d3..98cfebe 100644
--- a/crates/config/src/engine/general.rs
+++ b/crates/config/src/engine/general.rs
@@ -128,7 +128,8 @@ impl Engine {
     /// class_regex = "...", instance = "..." }, { floating = true,
     /// workspace = 2, x = .., y = .., width = .., height = ..,
     /// decorated = false, border_color = {r,g,b}, border_width = 2,
-    /// maximized = true, opacity = 0.9 })`. At least one matcher field is
+    /// corner_radius = 10, maximized = true, opacity = 0.9 })`. At least
+    /// one matcher field is
     /// required; unmatched rules apply nothing.
     ///
     /// `title`/`class` are plain substring/exact match, cheap and cover
@@ -182,6 +183,7 @@ impl Engine {
                     decorated: actions.get("decorated")?,
                     border_color,
                     border_width: actions.get("border_width")?,
+                    corner_radius: actions.get("corner_radius")?,
                     pinned: actions.get("pinned")?,
                     opacity: actions.get("opacity")?,
                     resize_margin: actions.get("resize_margin")?,
@@ -217,6 +219,22 @@ impl Engine {
         })?)
     }
 
+    /// Sets an environment variable in srdwm's own process - `std::process::
+    /// Command` inherits the parent's environment by default (`fn_spawn`
+    /// above never overrides that), so anything set here is visible to
+    /// every process `srd.spawn` starts from this point on, and to their own
+    /// children in turn. Hyprland's `env = NAME,VALUE` works the same way
+    /// (sets it in its own process before forking anything), which is the
+    /// mechanism a ported `env.conf` needs - there is no per-spawn
+    /// equivalent that would let one client see a variable no other client
+    /// does, so this is deliberately global and process-wide, not scoped.
+    pub(super) fn fn_setenv(&self) -> Result<mlua::Function<'_>> {
+        Ok(self.lua.create_function(move |_, (name, value): (String, String)| {
+            std::env::set_var(&name, &value);
+            Ok(())
+        })?)
+    }
+
     pub(super) fn fn_quit(&self) -> Result<mlua::Function<'_>> {
         let state = self.state.clone();
         Ok(self.lua.create_function(move |_, ()| {
diff --git a/crates/config/src/engine/register.rs b/crates/config/src/engine/register.rs
index abe919b..0cf64bc 100644
--- a/crates/config/src/engine/register.rs
+++ b/crates/config/src/engine/register.rs
@@ -17,6 +17,7 @@ impl Engine {
         srd.set("rule", self.fn_rule()?)?;
         srd.set("load", self.fn_load()?)?;
         srd.set("spawn", self.fn_spawn()?)?;
+        srd.set("setenv", self.fn_setenv()?)?;
         srd.set("notify", self.fn_notify()?)?;
         srd.set("quit", self.fn_quit()?)?;
         srd.set("reload", self.fn_reload()?)?;
@@ -44,6 +45,7 @@ impl Engine {
         window.set("set_decorations", self.fn_window_set_decorations()?)?;
         window.set("set_border_color", self.fn_window_set_border_color()?)?;
         window.set("set_border_width", self.fn_window_set_border_width()?)?;
+        window.set("set_corner_radius", self.fn_window_set_corner_radius()?)?;
         window.set("set_opacity", self.fn_window_set_opacity()?)?;
         window.set("set_resize_margin", self.fn_window_set_resize_margin()?)?;
         window.set("set_floating", self.fn_window_set_floating()?)?;
diff --git a/crates/config/src/engine/support.rs b/crates/config/src/engine/support.rs
index 9346499..0f83885 100644
--- a/crates/config/src/engine/support.rs
+++ b/crates/config/src/engine/support.rs
@@ -82,6 +82,7 @@ pub(super) fn validate(s: &SharedState) -> Vec<String> {
     check_range("layout.floating.gaps.outer", 0.0, 100.0);
     check_range("general.border_width", 0.0, 20.0);
     check_range("theme.decorations.border.width", 0.0, 20.0);
+    check_range("theme.decorations.border.radius", 0.0, 100.0);
     check_range("general.animation_duration", 0.0, 1000.0);
     check_range("general.resize_margin", 1.0, 50.0);
     check_range("performance.max_fps", 30.0, 240.0);
@@ -242,6 +243,7 @@ pub(super) fn default_config() -> HashMap<String, ConfigValue> {
     set("theme.colors.success", String("#a3be8c".into()));
 
     set("theme.decorations.border.width", Number(2.0));
+    set("theme.decorations.border.radius", Number(6.0));
     set("theme.decorations.border.active_color", String("#88c0d0".into()));
     set("theme.decorations.border.inactive_color", String("#2e3440".into()));
     set("theme.decorations.border.focused_style", String("solid".into()));
diff --git a/crates/config/src/engine/window.rs b/crates/config/src/engine/window.rs
index a7e6bf3..61e7b89 100644
--- a/crates/config/src/engine/window.rs
+++ b/crates/config/src/engine/window.rs
@@ -139,6 +139,20 @@ impl Engine {
         })?)
     }
 
+    pub(super) fn fn_window_set_corner_radius(&self) -> Result<mlua::Function<'_>> {
+        let state = self.state.clone();
+        Ok(self.lua.create_function(move |_, radius: u32| {
+            let wm = state.borrow().wm.clone();
+            let mut wm = wm.borrow_mut();
+            if let Some(id) = wm.focused_id() {
+                if let Some(w) = wm.window_mut(id) {
+                    w.corner_radius = radius;
+                }
+            }
+            Ok(())
+        })?)
+    }
+
     pub(super) fn fn_window_set_opacity(&self) -> Result<mlua::Function<'_>> {
         let state = self.state.clone();
         Ok(self.lua.create_function(move |_, opacity: f32| {