feat: add text underline offset to link Purmerend theme (#913)

**Added `text-underline-offset` to `Link`** 

<img width="600" alt="Screenshot 2025-01-06 at 15 47 43"
src="https://github.com/user-attachments/assets/bf1deb07-cd96-4091-b91b-944440085c5e"
/>

<img width="600" alt="Screenshot 2025-01-06 at 15 48 10"
src="https://github.com/user-attachments/assets/43e237ff-1417-4483-8e5b-763287ce05df"
/>

Volgens de voorbeeld in Gemeente Utrecht is de underline offset 3px. 

In progress ⬇️
- [ ] Er is nog een issue met de underline color (niet meer dark-mode)
- [x] Hover state underline thickness tokens toevoegen
- [x] Gaat het lukken om alles in de Basis thema te zetten ipv Purmerend
thema?

**Added `underline-thickness` hover state to `Link`**

<img width="600" alt="Screenshot 2025-01-07 at 11 28 50"
src="https://github.com/user-attachments/assets/494420e2-7727-4b06-9ed1-98a1587da122"
/>

Design token name `utrecht.link.hover.text-decoration-thickness` (3px)
geeft aan token reference could not be found, daarom staat het gewoon
hardcoded in als `3px`

---------

Co-authored-by: Marwa <[email protected]>
Co-authored-by: Robbert Broersma <[email protected]>

.changeset/fifty-jars-shave.md

@@ -0,0 +1,6 @@
+---
+"@nl-design-system-unstable/basis-design-tokens": patch
+"@nl-design-system-community/purmerend-design-tokens": patch
+---
+
+Use thicker underline for links on hover, and move underline slightly away from text.

proprietary/basis-design-tokens/figma/basis.tokens.json

@@ -3720,7 +3720,7 @@
         },
         "text-underline-offset": {
           "$type": "other",
-          "$value": "auto"
+          "$value": "3px"
         },
         "icon": {
           "size": {
@@ -3761,11 +3761,11 @@
           },
           "text-decoration": {
             "$type": "textDecoration",
-            "$value": "None"
+            "$value": "none"
           },
           "text-decoration-thickness": {
             "$type": "other",
-            "$value": "{utrecht.link.text-decoration-thickness}"
+            "$value": "3px"
           }
         },
         "visited": {