feat(ui): extend AdaptiveTextField and migrate travel form to use them

diff --git a/lib/pages/shopinbit/step_4_components/shopinbit_travel_form.dart b/lib/pages/shopinbit/step_4_components/shopinbit_travel_form.dart
index 16db676..80382eb 100644
--- a/lib/pages/shopinbit/step_4_components/shopinbit_travel_form.dart
+++ b/lib/pages/shopinbit/step_4_components/shopinbit_travel_form.dart
@@ -7,6 +7,7 @@ import "../../../providers/db/drift_provider.dart";
 import "../../../providers/global/shopin_bit_service_provider.dart";
 import "../../../utilities/text_styles.dart";
 import "../../../utilities/util.dart";
+import "../../../widgets/textfields/adaptive_text_field.dart";
 import "shopinbit_country_picker.dart";
 import "shopinbit_labeled_checkbox.dart";
 import "shopinbit_privacy_checkbox.dart";
@@ -14,7 +15,6 @@ import "shopinbit_step4_dropdown.dart";
 import "shopinbit_step4_header.dart";
 import "shopinbit_step4_submit.dart";
 import "shopinbit_step4_submit_button.dart";
-import "shopinbit_step4_text_field.dart";
 import "shopinbit_traveler_counter.dart";
 
 const String _exactDates = "Exact dates";
@@ -354,14 +354,16 @@ class _ShopInBitTravelFormState extends ConsumerState<ShopInBitTravelForm> {
           onChanged: (value) => setState(() => _selectedArrangement = value),
         ),
         SizedBox(height: isDesktop ? 24 : 16),
-        ShopInBitStep4TextField(
+        AdaptiveTextField(
           controller: _arrangementDetailsController,
           focusNode: _arrangementDetailsFocusNode,
-          hintText:
+          labelText:
               "Describe your specific requirements "
               "(luggage, cabin class, hotel stars, etc.)",
           minLines: 3,
           maxLines: 6,
+          autocorrect: false,
+          enableSuggestions: false,
           errorText: arrangementDetailsError,
           onChanged: (_) => setState(() {}),
         ),
@@ -376,19 +378,23 @@ class _ShopInBitTravelFormState extends ConsumerState<ShopInBitTravelForm> {
           hintText: "Departure country",
         ),
         SizedBox(height: isDesktop ? 24 : 16),
-        ShopInBitStep4TextField(
+        AdaptiveTextField(
           controller: _departureCityController,
           focusNode: _departureCityFocusNode,
-          hintText: "Departure city",
+          labelText: "Departure city",
+          autocorrect: false,
+          enableSuggestions: false,
           errorText: departureCityError,
           onChanged: (_) => setState(() {}),
         ),
         SizedBox(height: isDesktop ? 24 : 16),
-        ShopInBitStep4TextField(
+        AdaptiveTextField(
           controller: _destinationsController,
           focusNode: _destinationsFocusNode,
-          hintText: "Destination city",
+          labelText: "Destination city",
           enabled: !_needsRecommendations,
+          autocorrect: false,
+          enableSuggestions: false,
           errorText: destinationsError,
           onChanged: (_) => setState(() {}),
         ),
@@ -411,31 +417,35 @@ class _ShopInBitTravelFormState extends ConsumerState<ShopInBitTravelForm> {
         SizedBox(height: isDesktop ? 24 : 16),
 
         if (_selectedDateMode == _exactDates) ...[
-          ShopInBitStep4TextField(
+          AdaptiveTextField(
             controller: _departureDateController,
             focusNode: _departureDateFocusNode,
-            hintText: "DD/MM/YYYY",
             labelText: "Departure date",
+            hintText: "DD/MM/YYYY",
             readOnly: true,
             onTap: () => _pickDate(
               _departureDateController,
               () => _departureDateTouched = true,
             ),
-            suffixIcon: const Icon(Icons.calendar_today, size: 18),
+            suffixIcons: const [Icon(Icons.calendar_today, size: 18)],
+            autocorrect: false,
+            enableSuggestions: false,
             errorText: departureDateError,
           ),
           SizedBox(height: isDesktop ? 24 : 16),
-          ShopInBitStep4TextField(
+          AdaptiveTextField(
             controller: _returnDateController,
             focusNode: _returnDateFocusNode,
-            hintText: "DD/MM/YYYY",
             labelText: "Return date",
+            hintText: "DD/MM/YYYY",
             readOnly: true,
             onTap: () => _pickDate(
               _returnDateController,
               () => _returnDateTouched = true,
             ),
-            suffixIcon: const Icon(Icons.calendar_today, size: 18),
+            suffixIcons: const [Icon(Icons.calendar_today, size: 18)],
+            autocorrect: false,
+            enableSuggestions: false,
             errorText: returnDateError,
           ),
           SizedBox(height: isDesktop ? 24 : 16),
@@ -462,12 +472,14 @@ class _ShopInBitTravelFormState extends ConsumerState<ShopInBitTravelForm> {
             onChanged: (value) => setState(() => _selectedMonthSeason = value),
           ),
           SizedBox(height: isDesktop ? 24 : 16),
-          ShopInBitStep4TextField(
+          AdaptiveTextField(
             controller: _tripLengthController,
             focusNode: _tripLengthFocusNode,
-            hintText: "Number of nights",
+            labelText: "Number of nights",
             keyboardType: TextInputType.number,
             inputFormatters: [FilteringTextInputFormatter.digitsOnly],
+            autocorrect: false,
+            enableSuggestions: false,
             errorText: tripLengthError,
             onChanged: (_) => setState(() {}),
           ),
@@ -504,13 +516,15 @@ class _ShopInBitTravelFormState extends ConsumerState<ShopInBitTravelForm> {
         SizedBox(height: isDesktop ? 24 : 16),
         _TravelSectionLabel(text: "Budget", isDesktop: isDesktop),
         SizedBox(height: isDesktop ? 12 : 8),
-        ShopInBitStep4TextField(
+        AdaptiveTextField(
           controller: _travelBudgetController,
           focusNode: _travelBudgetFocusNode,
-          hintText: "Minimum 1000 EUR",
+          labelText: "Minimum 1000 EUR",
           keyboardType: TextInputType.number,
           inputFormatters: [FilteringTextInputFormatter.digitsOnly],
           suffixText: "EUR",
+          autocorrect: false,
+          enableSuggestions: false,
           errorText: travelBudgetError,
           onChanged: (_) => setState(() {}),
         ),
diff --git a/lib/widgets/textfields/adaptive_text_field.dart b/lib/widgets/textfields/adaptive_text_field.dart
index da30057..95d4543 100644
--- a/lib/widgets/textfields/adaptive_text_field.dart
+++ b/lib/widgets/textfields/adaptive_text_field.dart
@@ -13,23 +13,30 @@ class AdaptiveTextField extends StatefulWidget {
   const AdaptiveTextField({
     super.key,
     this.labelText,
+    this.hintText,
     this.controller,
     this.focusNode,
     this.autocorrect,
     this.readOnly = false,
+    this.enabled = true,
     this.enableSuggestions = true,
     this.onChanged,
     this.onChangedComprehensive,
     this.onSubmitted,
+    this.onTap,
     this.suffixIcons,
+    this.suffixText,
+    this.errorText,
     this.contentPadding,
     this.minLines,
     this.maxLines,
+    this.inputFormatters,
     this.showPasteClearButton = false,
     this.keyboardType,
   });
 
   final String? labelText;
+  final String? hintText;
 
   final TextEditingController? controller;
   final FocusNode? focusNode;
@@ -39,11 +46,13 @@ class AdaptiveTextField extends StatefulWidget {
   final int? maxLines;
 
   final bool readOnly;
+  final bool enabled;
   final bool enableSuggestions;
 
   final void Function(String)? onChanged;
   final void Function(String)? onChangedComprehensive;
   final void Function(String)? onSubmitted;
+  final VoidCallback? onTap;
 
   /// This will be ignored if [suffixIcons] is not null!
   final bool showPasteClearButton;
@@ -51,6 +60,15 @@ class AdaptiveTextField extends StatefulWidget {
   /// If this is not null, [showPasteClearButton] will be ignored.
   final List<Widget>? suffixIcons;
 
+  /// Optional trailing text rendered in the decoration's suffixText slot.
+  /// Ignored when [suffixIcons] is non-empty or [showPasteClearButton] is
+  /// true, since those occupy the same visual space.
+  final String? suffixText;
+
+  final String? errorText;
+
+  final List<TextInputFormatter>? inputFormatters;
+
   final TextInputType? keyboardType;
 
   @override
@@ -111,17 +129,27 @@ class _AdaptiveTextFieldState extends State<AdaptiveTextField> {
         controller: controller,
         focusNode: _focusNode,
         onChanged: widget.onChanged,
+        onTap: widget.onTap,
         readOnly: widget.readOnly,
+        enabled: widget.enabled,
         autocorrect: widget.autocorrect,
         enableSuggestions: widget.enableSuggestions,
         onSubmitted: widget.onSubmitted,
         keyboardType: widget.keyboardType,
+        inputFormatters: widget.inputFormatters,
         decoration:
             standardInputDecoration(
               widget.labelText,
               _focusNode,
               context,
             ).copyWith(
+              hintText: widget.hintText,
+              errorText: widget.errorText,
+              suffixText:
+                  (widget.suffixIcons?.isNotEmpty != true &&
+                      !widget.showPasteClearButton)
+                  ? widget.suffixText
+                  : null,
               contentPadding:
                   widget.contentPadding ??
                   (Util.isDesktop