UX-44: contract label says every 15 minutes, not hourly

The settings page contract choice read "Dynamic, hourly" / "Dynamisch,
per uur". Belgian day-ahead prices are per 15 minutes since 2025-10-01.
Now "Dynamic, every 15 minutes" / "Dynamisch, per kwartier". One DOCS
line that called dynamic pricing "hourly pricing" now says dynamic.
test_ui_text.py part 7 fails if either label says hourly again.

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

goodwe_controller/test_ui_text.py

@@ -286,6 +286,22 @@ check("app/uitext.py falls back to English per key and reads nl-BE as nl",
       and uitext._merge({"a": {"b": 1, "c": 2}}, {"a": {"b": 3}})
       == {"a": {"b": 3, "c": 2}})
 
+# ============================================================================ #
+print("\n7. the dynamic contract choice says 15 minutes, never hourly (UX-44)")
+# Belgian day-ahead prices are per 15 minutes since 2025-10-01.
+HOURLY = re.compile(r"hourly|per hour|\bhour\b|per uur|\buur\b|uurprijs",
+                    re.I)
+_dyn = {"en": EN["choices"]["contract"]["dynamic"],
+        "nl": NL["choices"]["contract"]["dynamic"]}
+check(f"the label reads 'Dynamic, every 15 minutes' / 'Dynamisch, per "
+      f"kwartier' ({_dyn})",
+      _dyn == {"en": "Dynamic, every 15 minutes",
+               "nl": "Dynamisch, per kwartier"})
+check("neither language calls the dynamic contract hourly",
+      not any(HOURLY.search(t) for t in _dyn.values()))
+check("mutation: the old labels are caught",
+      all(HOURLY.search(t) for t in ("Dynamic, hourly", "Dynamisch, per uur")))
+
 print()
 if fails:
     print(f"{len(fails)} FAILED")