Bugfix: Gridview whitespace autosize (#10118)

* Bugfix: Gridview whitespace autosize

* Fix large scale

* Fix viewoption sizes

* Add changelog

* Update unittests

* WIP

* Solution?

* WIP

* WIP

* Remove dev leftover

* cleanup code

* Calculate max tiles count per row / still needs to be recalculated when the slider value changes

* Implement watch for tile-size slider changes

* Rename rowCount

* Lint, change var to const, remove unnecessary computed

* Hide from screen readers

* feat: introduce useTileSize composable and watch that for tile sizes

* Fix undefined issues

* slim mount function

* fix: tile pixels and ghost tile count

* test: fix viewOptions unit tests

* Fixing ResourceTiles.spec.ts tests (WIP)

* Fix ResourceTiles.spec.ts

* Remove dev leftover

---------

Co-authored-by: Jan Ackermann <jan.alexander.ackermann@outlook.com>
Co-authored-by: Benedikt Kulmann <benedikt@kulmann.biz>

theming/_index.md

@@ -307,7 +307,9 @@ Size variables get prepended with `--oc-size-`, so e.g. _"icon-default"_ creates
     "icon-default": "",
     "max-height-logo": "",
     "max-width-logo": "",
-    "width-medium": ""
+    "width-medium": "",
+    "tiles-default": "",
+    "tiles-resize-step": ""
   }
 }
 ```
@@ -426,7 +428,9 @@ A full template for your custom theme is provided below, and you can use the ins
             "icon-default": "",
             "max-height-logo": "",
             "max-width-logo": "",
-            "width-medium": ""
+            "width-medium": "",
+            "tiles-default": "",
+            "tiles-resize-step": ""
           },
           "spacing": {
             "xsmall": "",