cgen: fix const fixed array with type alias (fix #24936) (#24946)

Author: Krchi

vlib/v/gen/c/cgen.v

@@ -5479,7 +5479,7 @@ fn (mut g Gen) cast_expr(node ast.CastExpr) {
 		if node_typ_is_option {
 			g.expr_with_opt(node.expr, expr_type, node.typ)
 		} else {
-			if node.expr is ast.ArrayInit && g.assign_op != .decl_assign {
+			if node.expr is ast.ArrayInit && g.assign_op != .decl_assign && !g.inside_const {
 				g.write('(${g.styp(node.expr.typ)})')
 			}
 			g.expr(node.expr)

vlib/v/tests/consts/const_fixed_array_with_type_alias_test.v

@@ -0,0 +1,14 @@
+pub const k_palette_colors = [Pixel([u8(255), 255, 255]!), Pixel([u8(192), 192, 192]!),
+	Pixel([u8(96), 96, 96]!), Pixel([u8(0), 0, 0]!)]
+
+pub type Pixel = [3]u8
+pub type Palette = []Pixel
+
+fn test_main() {
+	a := Palette(k_palette_colors)
+
+	assert a[0] == [u8(255), 255, 255]!
+	assert a[1] == [u8(192), 192, 192]!
+	assert a[2] == [u8(96), 96, 96]!
+	assert a[3] == [u8(0), 0, 0]!
+}