Add desktop integration files and window state persistence

outlay-gtk/src/window.rs

@@ -1,4 +1,5 @@
 use adw::prelude::*;
+use gtk::glib;
 use outlay_core::db::Database;
 use std::rc::Rc;
 
@@ -114,14 +115,52 @@ impl MainWindow {
         split_view.set_sidebar(Some(&sidebar_page));
         split_view.set_content(Some(&content_page));
 
+        // Restore window size from settings
+        let saved_width: i32 = db
+            .get_setting("window_width")
+            .ok()
+            .flatten()
+            .and_then(|s| s.parse().ok())
+            .unwrap_or(900);
+        let saved_height: i32 = db
+            .get_setting("window_height")
+            .ok()
+            .flatten()
+            .and_then(|s| s.parse().ok())
+            .unwrap_or(600);
+        let saved_maximized: bool = db
+            .get_setting("window_maximized")
+            .ok()
+            .flatten()
+            .map(|s| s == "true")
+            .unwrap_or(false);
+
         let window = adw::ApplicationWindow::builder()
             .application(app)
             .title("Outlay")
-            .default_width(900)
-            .default_height(600)
+            .default_width(saved_width)
+            .default_height(saved_height)
             .content(&split_view)
             .build();
 
+        if saved_maximized {
+            window.maximize();
+        }
+
+        // Save window size on close
+        {
+            let db_ref = db.clone();
+            window.connect_close_request(move |win| {
+                let (width, height) = win.default_size();
+                db_ref.set_setting("window_width", &width.to_string()).ok();
+                db_ref.set_setting("window_height", &height.to_string()).ok();
+                db_ref
+                    .set_setting("window_maximized", if win.is_maximized() { "true" } else { "false" })
+                    .ok();
+                glib::Propagation::Proceed
+            });
+        }
+
         MainWindow {
             window,
             split_view,