🐛 Fix typography style creation with tokenized line-height (#9121)

When a text element has a line-height coming from a design token, the value
may be a number (e.g. 1.5) and fails frontend data validation expecting a
string. Normalize line-height before creating the typography style so the
operation succeeds without throwing an assertion error.

Signed-off-by: juan-flores077 <toptalent399@gmail.com>

CHANGES.md

@@ -78,7 +78,7 @@
 - Fix copy to be more specific [Taiga #13990](https://tree.taiga.io/project/penpot/issue/13990)
 - Allow deleting the profile avatar after uploading [Github #9067](https://github.com/penpot/penpot/issues/9067)
 - Fix incorrect rendering when exporting text as SVG, PNG and JPG (by @edwin-rivera-dev) [Github #8516](https://github.com/penpot/penpot/issues/8516)
-
+- Fix typography style creation with tokenized line-height (by @juan-flores077) [Github #8479](https://github.com/penpot/penpot/issues/8479)
 
 ## 2.16.0 (Unreleased)
 

frontend/src/app/main/data/workspace/texts.cljs

@@ -935,6 +935,12 @@
                             (d/concat-vec txt/text-font-attrs
                                           txt/text-spacing-attrs
                                           txt/text-transform-attrs)))
+             values    (cond-> values
+                         (number? (:line-height values))
+                         (update :line-height str)
+
+                         (number? (:letter-spacing values))
+                         (update :letter-spacing str))
 
              typ-id    (uuid/next)
              typ       (-> (if multiple?