style: format the repo with prettier (green format:check)

`npm run format:check` (a CI gate) had drifted red across 44 files — pre-existing
files plus recently-added ones committed without formatting. Ran `prettier --write .`;
no logic changes. Also regenerates documentation.json (compodoc reflects the reformatted
component sources).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/beheer/domain/stamdata.ts

@@ -116,9 +116,13 @@ export function toJson(table: StamTable, rows: readonly StamRow[]): string {
     for (const c of table.columns) {
       const cell = (row[c.name] ?? '').trim();
       out[c.name] =
-        cell === '' ? (c.type === 'text' || c.type === 'enum' ? '' : null)
-        : c.type === 'number' ? Number(cell)
-        : cell;
+        cell === ''
+          ? c.type === 'text' || c.type === 'enum'
+            ? ''
+            : null
+          : c.type === 'number'
+            ? Number(cell)
+            : cell;
     }
     return out;
   });