Add named keyboard binding modes (#32)

Add named keyboard shortcut maps with an Escape exit and a panel indicator. Keep press/release ownership across transitions, validate remapped Escape keys, and cancel stale repeats and focus previews.

Give the indicator ownership of the panel while a mode is active. Close popovers, collapse Morph, and keep Live Activities data current without resizing the hidden panel. Document configuration and transition behavior.

Validation: 1,519 workspace Rust tests passed; 70 Python tests passed. Workspace build, formatting, Clippy, and Settings configuration validation passed. Opt-in native desktop checks were not rerun because Weston is absent.

Related: #5.

compositor/src/config.rs

@@ -15,6 +15,7 @@ pub(crate) use self::loading::{prepare, prepare_document, read_source, startup};
 pub(crate) use self::xwayland::{XwaylandConfig, XwaylandStartup};
 use appearance::*;
 pub use appearance::{BorderGradient, FocusEffectSettings, MaterialStyle, ThemeSettings};
+pub(crate) use bindings::BindingModes;
 use bindings::*;
 pub use bindings::{Binding, BindingAction};
 pub(crate) use bindings::{BindingSet, physical_keymap};
@@ -62,6 +63,8 @@ pub struct Config {
     #[serde(default)]
     bindings: Vec<BindingConfig>,
     #[serde(default)]
+    binding_modes: Vec<BindingModeConfig>,
+    #[serde(default)]
     window_rules: Vec<WindowRuleConfig>,
     #[serde(default)]
     scrolling: ScrollingConfig,
@@ -130,6 +133,7 @@ impl Config {
         }
         let input_settings = self.input_settings()?;
         let bindings = self.bindings(&input_settings)?;
+        let binding_modes = self.binding_modes(&input_settings, &bindings)?;
         Ok(crate::RuntimeConfig {
             activity_settings: self.activities.clone(),
             activity_matcher: ferese_config::activities::Matcher::new(&self.activities)
@@ -142,6 +146,7 @@ impl Config {
             gap_config: self.gap_config()?,
             input_settings,
             bindings,
+            binding_modes,
             window_rules: self.window_rules()?,
             theme_settings: self.theme_settings()?,
             panel_style: self