fix(#129): peaufiner le wizard famille (co-parent, hauteurs, à naître).

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/lib/widgets/admin/common/validation_detail_section.dart

@@ -35,19 +35,23 @@ class ValidationFormMetrics {
   );
 
   static double get sectionTitleBlockHeight =>
-      sectionTitleFontSize + sectionTitleGapBelow;
+      sectionTitleFontSize * 1.25 + sectionTitleGapBelow;
 
+  /// Libellé : marge au-dessus de [fieldLabelFontSize] (métriques police).
   static double get labeledRowHeight =>
-      fieldLabelFontSize + fieldLabelGapBelow + fieldHeight + rowGapBelow;
+      fieldLabelFontSize * 1.25 +
+      fieldLabelGapBelow +
+      fieldHeight +
+      rowGapBelow;
 
-  /// Corps modale AM : padding wizard + titre + [rows] lignes + nav.
+  /// Corps modale AM / famille : padding wizard + titre + [rows] lignes + nav.
   static double shellBodyHeightForRows(int rows) =>
       20 * 2 + // padding wizard
       4 + // espace haut
       sectionTitleBlockHeight +
       rows * labeledRowHeight +
       24 + // avant nav
-      44; // boutons
+      48; // boutons (+ marge anti-overflow)
 }
 
 /// Bloc type formulaire (titre de section + champs read-only) pour les modales de validation.
@@ -134,6 +138,7 @@ class ValidationFormGrid extends StatelessWidget {
               label: f.label,
               field: f.field,
               expand: expandVertically,
+              labelTrailing: f.labelTrailing,
             ),
           )
           .toList();
@@ -262,28 +267,37 @@ class ValidationLabeledField extends StatelessWidget {
   final String label;
   final Widget field;
   final bool expand;
+  /// Widget aligné à droite sur la ligne du libellé (ex. switch « Même adresse »).
+  final Widget? labelTrailing;
 
   const ValidationLabeledField({
     super.key,
     required this.label,
     required this.field,
     this.expand = false,
+    this.labelTrailing,
   });
 
   @override
   Widget build(BuildContext context) {
+    final labelStyle = TextStyle(
+      fontSize: ValidationFormMetrics.fieldLabelFontSize,
+      fontWeight: FontWeight.w500,
+      color: Colors.grey.shade700,
+    );
     return Column(
       crossAxisAlignment: CrossAxisAlignment.start,
       mainAxisSize: expand ? MainAxisSize.max : MainAxisSize.min,
       children: [
-        Text(
-          label,
-          style: TextStyle(
-            fontSize: ValidationFormMetrics.fieldLabelFontSize,
-            fontWeight: FontWeight.w500,
-            color: Colors.grey.shade700,
+        if (labelTrailing == null)
+          Text(label, style: labelStyle)
+        else
+          Row(
+            children: [
+              Expanded(child: Text(label, style: labelStyle)),
+              labelTrailing!,
+            ],
           ),
-        ),
         SizedBox(height: ValidationFormMetrics.fieldLabelGapBelow),
         if (expand) Expanded(child: field) else field,
       ],
@@ -299,6 +313,7 @@ class ValidationEditableField extends StatelessWidget {
   final String? hintText;
   final int maxLines;
   final bool compact;
+  final bool enabled;
 
   const ValidationEditableField({
     super.key,
@@ -308,6 +323,7 @@ class ValidationEditableField extends StatelessWidget {
     this.hintText,
     this.maxLines = 1,
     this.compact = false,
+    this.enabled = true,
   });
 
   static const double _compactFieldHeight = 34;
@@ -339,6 +355,7 @@ class ValidationEditableField extends StatelessWidget {
     if (maxLines > 1) {
       return TextField(
         controller: controller,
+        enabled: enabled,
         keyboardType: keyboardType,
         inputFormatters: inputFormatters,
         maxLines: maxLines,
@@ -350,6 +367,7 @@ class ValidationEditableField extends StatelessWidget {
       return _validationFieldFillHeight(
         TextField(
           controller: controller,
+          enabled: enabled,
           keyboardType: keyboardType,
           inputFormatters: inputFormatters,
           maxLines: 1,
@@ -365,6 +383,7 @@ class ValidationEditableField extends StatelessWidget {
         decoration: _compactDecoration(),
         child: TextField(
           controller: controller,
+          enabled: enabled,
           keyboardType: keyboardType,
           inputFormatters: inputFormatters,
           maxLines: 1,
@@ -381,13 +400,15 @@ class ValidationEditableField extends StatelessWidget {
   }
 }
 
-/// Étire le champ si le parent impose une hauteur (grille [expandVertically]).
+/// Hauteur TF fixe ; en grille [expandVertically], étire jusqu’à la hauteur dispo.
 Widget _validationFieldFillHeight(Widget field) {
   return LayoutBuilder(
     builder: (context, c) {
-      if (!c.hasBoundedHeight || !c.maxHeight.isFinite) return field;
+      final h = (c.hasBoundedHeight && c.maxHeight.isFinite)
+          ? c.maxHeight
+          : ValidationFormMetrics.fieldHeight;
       return SizedBox(
-        height: c.maxHeight,
+        height: h,
         width: double.infinity,
         child: field,
       );
@@ -481,12 +502,14 @@ class ValidationPostalCodeField extends StatefulWidget {
   final TextEditingController controller;
   final String? hintText;
   final bool allowEmpty;
+  final bool enabled;
 
   const ValidationPostalCodeField({
     super.key,
     required this.controller,
     this.hintText,
     this.allowEmpty = false,
+    this.enabled = true,
   });
 
   @override
@@ -536,6 +559,7 @@ class _ValidationPostalCodeFieldState extends State<ValidationPostalCodeField> {
         key: _fieldKey,
         controller: widget.controller,
         focusNode: _focusNode,
+        enabled: widget.enabled,
         keyboardType: TextInputType.number,
         textInputAction: TextInputAction.next,
         textAlignVertical: TextAlignVertical.center,