fix(android): draw the search hint ourselves, TextPrompt needs a style object

Dark.style has no object for the prompt text, so the search field sat there
empty and mute. A label inside the field, hit-test off so the tap goes
through, shown only while the field is empty.

Fourth time today the same conclusion: whatever FMX renders through a style
template may or may not exist in the style actually loaded. Built explicitly,
it is there.

Also noted: the row height was never wrong. 56 logical units on a 3x display
are the ~166 device pixels the screenshot showed - only the second line was
missing.

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

mainApk.pas

@@ -98,6 +98,7 @@ type
     // --- ecran 2 : liste
     FLayList: TLayout;
     FSearch: TEdit;
+    FSearchHint: TLabel;
     FFolderBox: TComboBox;
     FList: TListBox;
     FCount: TLabel;
@@ -398,8 +399,19 @@ begin
   FSearch := TEdit.Create(Self);
   FSearch.Parent := LTop;
   FSearch.Align := TAlignLayout.Client;
-  FSearch.TextPrompt := 'Rechercher';
   FSearch.OnChangeTracking := OnSearchChanged;
+
+  // Invite dessinee par nous, pas par TextPrompt : Dark.style ne comporte pas
+  // l'objet que le style est cense fournir pour l'afficher, et le champ
+  // restait donc vide et muet. HitTest desactive pour que le clic traverse
+  // jusqu'au champ.
+  FSearchHint := TLabel.Create(FSearch);
+  FSearchHint.Parent := FSearch;
+  FSearchHint.Align := TAlignLayout.Client;
+  FSearchHint.Margins.Left := 10;
+  FSearchHint.HitTest := False;
+  FSearchHint.Opacity := 0.45;
+  FSearchHint.Text := 'Rechercher';
 end;
 
 /// Intitule discret au-dessus d'une valeur. Meme forme pour toutes les
@@ -1163,6 +1175,7 @@ begin
   // quelques centaines d'entrees c'est imperceptible ; passer a un modele
   // virtuel (TListView) le jour ou ca rame.
   Touch;
+  FSearchHint.Visible := FSearch.Text = '';
   LFolder := '';
   if FFolderBox.ItemIndex > 0 then   // 0 = tous les dossiers
     LFolder := FFolderBox.Items[FFolderBox.ItemIndex];