Add tileSize field for raster and raster-dem tile sources (#946) (#947)

## Launch Checklist

Add `tileSize` field for raster and raster-dem tile sources. Solves #946


![Untitled](https://github.com/user-attachments/assets/833bf41b-0439-47f3-b9ff-5f289f437725)

### Not in this PR

i18n for `Tile Size`

 - [x] Briefly describe the changes in this PR.
 - [x] Link to related issues.
- [x] Include before/after visuals or gifs if this PR includes visual
changes.
 - [x] Write tests for all new functionality.
 - [x] Add an entry to `CHANGELOG.md` under the `## main` section.

---------

Co-authored-by: Harel M <harel.mazor@gmail.com>
Co-authored-by: Keitaroh Kobayashi <keita@kbys.me>
Co-authored-by: Hugues Tavernier <hugues.tavernier@protonmail.com>
Co-authored-by: Joscha <34318751+josxha@users.noreply.github.com>

src/locales/de/translation.json

@@ -163,6 +163,7 @@
   "Add a new source to your style. You can only choose the source type and id at creation time!": "Füge eine neue Quelle zu deinem Stil hinzu. Du kannst den Quellentyp und die ID nur bei der Erstellung auswählen!",
   "TileJSON URL": "TileJSON URL",
   "Tile URL": "Kachel-URL",
+  "Scheme Type": "Schema-Typ",
   "Coord top left": "Koordinate oben links",
   "Coord top right": "Koordinate oben rechts",
   "Coord bottom right": "Koordinate unten rechts",
@@ -172,6 +173,7 @@
   "GeoJSON URL": "GeoJSON URL",
   "GeoJSON": "GeoJSON",
   "Cluster": "Cluster",
+  "Tile Size": "Kachelgröße",
   "Encoding": "Kodierung",
   "Error:": "Fehler:",
   "MapTiler Access Token": "MapTiler Zugriffstoken",