fix: fix value retrieval in get_value and enhance SVG gradient parsing

Author: yuanchuan

src/generator/svg-gradient.js

@@ -15,6 +15,13 @@ export default function create_svg_gradient(type, args) {
     } else if (/^(rotate|translate|scale|skewX|skewY|matrix)\s*\(/.test(first)) {
       transform = `gradientTransform: ${first};`;
     }
+
+    if (values.length == 1 && first.indexOf(',') > -1) {
+       let groups = parse_value_group(first, { noSpace: true });
+       if (groups.length > 1) {
+         values = groups;
+       }
+    }
   }
 
   if (transform) {

src/utils/index.js

@@ -77,6 +77,9 @@ export function cell_id(x, y, z) {
 export function get_value(input) {
   let v = input;
   while (v && !is_nil(v.value)) v = v.value;
+  if (typeof v == 'object' && 'value' in v) {
+    return v.value ?? '';
+  }
   return v ?? '';
 }