chore(cosmic-theme): move Roundness to libcosmic

cosmic-theme/src/model/spacing.rs

@@ -41,3 +41,59 @@ impl Default for Spacing {
         }
     }
 }
+
+/// Density options for the Cosmic theme
+#[derive(Copy, Clone, Debug, Default, Eq, PartialEq, Serialize, Deserialize)]
+pub enum Density {
+    /// Lower padding/spacing of elements
+    Compact,
+    /// Standard padding/spacing of elements
+    #[default]
+    Standard,
+    /// Higher padding/spacing of elements
+    Spacious,
+}
+
+impl From<Density> for Spacing {
+    fn from(value: Density) -> Self {
+        match value {
+            Density::Compact => Spacing {
+                space_none: 0,
+                space_xxxs: 4,
+                space_xxs: 4,
+                space_xs: 8,
+                space_s: 8,
+                space_m: 16,
+                space_l: 24,
+                space_xl: 32,
+                space_xxl: 48,
+                space_xxxl: 64,
+            },
+            Density::Standard => Spacing::default(),
+            Density::Spacious => Spacing {
+                space_none: 4,
+                space_xxxs: 8,
+                space_xxs: 12,
+                space_xs: 16,
+                space_s: 24,
+                space_m: 32,
+                space_l: 48,
+                space_xl: 64,
+                space_xxl: 128,
+                space_xxxl: 160,
+            },
+        }
+    }
+}
+
+impl From<Spacing> for Density {
+    fn from(value: Spacing) -> Self {
+        if value.space_m.saturating_sub(16) == 0 {
+            Self::Compact
+        } else if value.space_m.saturating_sub(24) == 0 {
+            Self::Standard
+        } else {
+            Self::Spacious
+        }
+    }
+}