Advance redbear-full Wayland, greeter, and Qt integration

Consolidate the active desktop path around redbear-full while landing the greeter/session stack and the runtime fixes needed to keep Wayland and KWin bring-up moving forward.

local/recipes/system/redbear-sessiond/source/src/runtime_state.rs

@@ -0,0 +1,34 @@
+use std::sync::{Arc, RwLock};
+
+#[derive(Clone, Debug)]
+pub struct SessionRuntime {
+    pub session_id: String,
+    pub seat_id: String,
+    pub username: String,
+    pub uid: u32,
+    pub vt: u32,
+    pub leader: u32,
+    pub state: String,
+    pub active: bool,
+}
+
+impl Default for SessionRuntime {
+    fn default() -> Self {
+        Self {
+            session_id: String::from("c1"),
+            seat_id: String::from("seat0"),
+            username: String::from("root"),
+            uid: 0,
+            vt: 3,
+            leader: std::process::id(),
+            state: String::from("online"),
+            active: true,
+        }
+    }
+}
+
+pub type SharedRuntime = Arc<RwLock<SessionRuntime>>;
+
+pub fn shared_runtime() -> SharedRuntime {
+    Arc::new(RwLock::new(SessionRuntime::default()))
+}