Add example-name hint to the preset-name keyboard

The preset-name keypad (used both when adding a preset via manual
coordinates and after an address search) only showed "Name
(optional):" with no indication of what kind of name was expected.
Adds a localized hint line with example names (e.g. "Home, Work,
Holiday home") under the title in both runPresetNameKeypad()
(location_presets_screen.cpp) and runNameKeypad()
(address_search_screen.cpp), measuring the header height dynamically
via getCursorY() the same way runAddressKeyboard() already does, so
the input field and keyboard shift down to make room regardless of
translation length.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/i18n.h

@@ -268,6 +268,13 @@ enum class StringId : uint8_t {
     FIRST_RUN_COMPLETE_BODY1,
     FIRST_RUN_COMPLETE_BODY2,
 
+    // Hinweis mit Beispielnamen unter dem Titel der Namens-Tastatur
+    // (location_presets_screen.cpp::runPresetNameKeypad UND
+    // address_search_screen.cpp::runNameKeypad, beide spiegeln sich) -
+    // ohne jeden Hinweis wussten Einsteiger nicht, was fuer ein Name hier
+    // gemeint ist (Preset-Name wie "Zuhause", nicht z.B. ein Ort/Adresse).
+    LOCATION_NAME_HINT,
+
     COUNT
 };