refactor(shell/element): refactor how decorations height is accessed

This fixes several things:
- The xwayland code previously incorrectly used the SSD_HEIGHT (for Windows) even when the X11 surface was in a stack
- The SSD_HEIGHT was defined in surface.rs, even though rendering serverside decorations is done in the window/stack

Rename (min|max)_size to (min|max)_size_without_ssd in CosmicSurface and make it act accordingly
Add a new (min|max)_size() in CosmicWindow and CosmicStack, which takes the surface's (min|max)_size and adds the decorations.
Change all callers to use (min|max)_size() from the window or stack respectively, except is_dialog() where it does not matter.

src/shell/element/window.rs

@@ -55,10 +55,10 @@ use std::{
 };
 use wayland_backend::server::ObjectId;
 
-use super::{
-    surface::{RESIZE_BORDER, SSD_HEIGHT},
-    CosmicSurface,
-};
+use super::CosmicSurface;
+
+pub const SSD_HEIGHT: i32 = 36;
+pub const RESIZE_BORDER: i32 = 10;
 
 #[derive(Clone, PartialEq, Eq, Hash)]
 pub struct CosmicWindow(pub(super) IcedElement<CosmicWindowInternal>);
@@ -386,6 +386,29 @@ impl CosmicWindow {
     pub(crate) fn force_redraw(&self) {
         self.0.force_redraw();
     }
+
+    pub fn min_size(&self) -> Option<Size<i32, Logical>> {
+        self.0
+            .with_program(|p| p.window.min_size_without_ssd())
+            .map(|size| {
+                if self.0.with_program(|p| !p.window.is_decorated(false)) {
+                    size + (0, SSD_HEIGHT).into()
+                } else {
+                    size
+                }
+            })
+    }
+    pub fn max_size(&self) -> Option<Size<i32, Logical>> {
+        self.0
+            .with_program(|p| p.window.max_size_without_ssd())
+            .map(|size| {
+                if self.0.with_program(|p| !p.window.is_decorated(false)) {
+                    size + (0, SSD_HEIGHT).into()
+                } else {
+                    size
+                }
+            })
+    }
 }
 
 #[derive(Debug, Clone, Copy)]