feat: add support for dark / light mode switching (#178)

* feat: add support for dark / light mode switching and simultaneouscustom light / dark mode themes

* refactor(color-picker): optional initial color and fallback color

* refactor: used FixedPortion for layout of the settings item

This makes sure that the control always has at least the specified portion of the available space

* refactor: make all members of the ThemeBuilder public

* refactor: add and update palette colors

* fix(theme): typo and derive PartialEq for ThemeBuilder

* fix: update color picker usage

* feat: add more variables to the theme

* fix: radius on headerbar

* fix: Theme CosmicConfigEntry impl

* chore: specify rev of taffy

* fix: theme CosmicConfigEntry missing variables

* fix: apply theme type when theme mode changes

* wip: add plus icon to empty color picker button

* chore: fix rev and imports

* refactor(color-picker): allow custom size for the icon

* refactor(color_picker): make color_button public

* update iced

cosmic-theme/src/model/dark.ron

@@ -55,6 +55,15 @@ Dark (
         neutral_10: (
             c: "#FFFFFF",
         ),
+        bright_green: (
+            c: "#5EDB8C",
+        ),
+        bright_red: (
+            c: "#FFA090",
+        ),
+        bright_orange: (
+            c: "#FFA37D",
+        ),
         ext_warm_grey: (
             c: "#9B8E8A",
         ),
@@ -76,23 +85,32 @@ Dark (
         ext_indigo: (
             c: "#3E88FF",
         ),
+        accent_blue: (
+            c: "#63D0DF",
+        ),
+        accent_green: (
+            c: "#92CF9C",
+        ),
         accent_warm_grey: (
-            c: "#554742",
+            c: "#CABAB4",
         ),
         accent_orange: (
-            c: "#AF5C02",
+            c: "#FFAD00",
         ),
         accent_yellow: (
-            c: "#966800",
+            c: "#F7E062",
         ),
         accent_purple: (
-            c: "#813FFF",
+            c: "#E79CFE",
         ),
         accent_pink: (
-            c: "#F93A83",
+            c: "#FF9CB1",
+        ),
+        accent_red: (
+            c: "#FDA1A0",
         ),
         accent_indigo: (
-            c: "#3E88FF",
+            c: "#A1C0EB",
         ),
     )
-)
+)