Restore previous theme toggle icons

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: MariusStorhaug

.github/zensical.toml

@@ -26,23 +26,23 @@ features = [
 
 [[project.theme.palette]]
 media = "(prefers-color-scheme)"
-toggle.icon = "material/link"
+toggle.icon = "lucide/sun-moon"
 toggle.name = "Switch to dark mode"
 
 [[project.theme.palette]]
 media = "(prefers-color-scheme: dark)"
 scheme = "slate"
 primary = "black"
 accent = "light blue"
-toggle.icon = "material/toggle-switch-off-outline"
+toggle.icon = "lucide/moon"
 toggle.name = "Switch to light mode"
 
 [[project.theme.palette]]
 media = "(prefers-color-scheme: light)"
 scheme = "default"
 primary = "black"
 accent = "light blue"
-toggle.icon = "material/toggle-switch"
+toggle.icon = "lucide/sun"
 toggle.name = "Switch to system preference"
 
 [project.theme.icon]