🚸 [#319] feat: Change label and order of ProcesType options

IMHO, having the "nummer" first gives better UX, because the user knows
the number they need by heart, and the most recent jaar is most often
needed.

```python
   return OBOption(label=f"{arg.nummer} - {arg.jaar} - {arg.naam}", value=arg.url)
```

Author: CharString

backend/src/openbeheer/types/_open_beheer.py

@@ -209,7 +209,7 @@ def fetch_procestype_options():
 
     procestypen = decode(response.content, type=list[LAXProcesType])
     return [
-        as_ob_option(p) for p in sorted(procestypen, key=lambda v: (-v.jaar, v.naam))
+        as_ob_option(p) for p in sorted(procestypen, key=lambda v: (-v.jaar, v.nummer))
     ]
 
 
@@ -783,7 +783,7 @@ class ExpandableZaakType(ZaakTypeWithUUID, Struct):
 
 @as_ob_option.register
 def _lax_procestype_as_option(arg: ProcesType) -> OBOption[str | None]:
-    return OBOption(label=f"{arg.naam} - {arg.jaar}", value=arg.url)
+    return OBOption(label=f"{arg.jaar} - {arg.nummer} - {arg.naam}", value=arg.url)
 
 
 # Types from read only (or not implemented CUD) API's

backend/src/openbeheer/zaaktype/tests/test_zaaktype_detail.py

@@ -770,12 +770,8 @@ def test_selectielijst_procestype_options(self):
             # Value should be a URL
             self.assertIn("https://", value)
 
-            # Within same year, should be sorted alphabetically
-            if year == previous_year:
-                self.assertGreater(label, previous_label)
             # Years should be descending.
-            else:
-                self.assertLess(year, previous_year)
+            self.assertLessEqual(year, previous_year)
 
             previous = option