fix(select): improve screen reader announcement timing for validation errors (#30723)

Issue number: internal

---------

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## What is the current behavior?
<!-- Please describe the current behavior that you are modifying. -->

Currently, when an error text is shown, it may not announce itself to
voice assistants. This is because the way error text currently works is
by always existing in the DOM, but being hidden when there is no error.
When the error state changes, the error text is shown, but as far as the
voice assistant can tell it's always been there and nothing has changed.

## What is the new behavior?
<!-- Please describe the behavior or changes that are being added by
this PR. -->

- Updated aria attributes
- Added observer with an observer

We had to do this with a mutation observer and state because it's
important in some frameworks, like Angular, that state changes to cause
a re-render. This, combined with some minor aria changes, makes it so
that when a field is declared invalid, it immediately announces the
invalid state instead of waiting for the user to go back to the invalid
field.

## Does this introduce a breaking change?

- [ ] Yes
- [x] No

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  2. Update the BREAKING.md file with the breaking change.
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## Other information

<!-- Any other information that is important to this PR such as
screenshots of how the component looks before and after the change. -->


[Preview](https://ionic-framework-git-fw-6797-ionic1.vercel.app/src/components/select/test/validation/)

packages/angular/test/base/src/app/lazy/template-form/template-form.component.html

@@ -77,6 +77,31 @@
           <p>MinLength Errors: <span id="minlength-errors">{{minLengthField.errors | json}}</span></p>
         </ion-label>
       </ion-item>
+
+      <!-- Test ion-select with required validation -->
+      <ion-item>
+        <ion-select
+          label="Required Select"
+          [(ngModel)]="selectValue"
+          name="selectField"
+          required
+          #selectField="ngModel"
+          id="template-select-test"
+          errorText="This field is required"
+          helperText="Select an option">
+          <ion-select-option value="option1">Option 1</ion-select-option>
+          <ion-select-option value="option2">Option 2</ion-select-option>
+        </ion-select>
+      </ion-item>
+      
+      <!-- Display validation state for debugging -->
+      <ion-item>
+        <ion-label>
+          <p>Select Touched: <span id="select-touched">{{selectField.touched}}</span></p>
+          <p>Select Invalid: <span id="select-invalid">{{selectField.invalid}}</span></p>
+          <p>Select Errors: <span id="select-errors">{{selectField.errors | json}}</span></p>
+        </ion-label>
+      </ion-item>
     </ion-list>
 
     <div class="ion-padding">

packages/angular/test/base/src/app/lazy/template-form/template-form.component.ts

@@ -9,6 +9,7 @@ export class TemplateFormComponent {
   inputValue = '';
   textareaValue = '';
   minLengthValue = '';
+  selectValue = '';
   
   // Track if form has been submitted
   submitted = false;

packages/angular/test/base/src/app/standalone/app-standalone/app.routes.ts

@@ -47,6 +47,7 @@ export const routes: Routes = [
         children: [
           { path: 'input-validation', loadComponent: () => import('../validation/input-validation/input-validation.component').then(c => c.InputValidationComponent) },
           { path: 'textarea-validation', loadComponent: () => import('../validation/textarea-validation/textarea-validation.component').then(c => c.TextareaValidationComponent) },
+          { path: 'select-validation', loadComponent: () => import('../validation/select-validation/select-validation.component').then(c => c.SelectValidationComponent) },
           { path: '**', redirectTo: 'input-validation' }
         ]
       },

packages/angular/test/base/src/app/standalone/home-page/home-page.component.html

@@ -131,6 +131,11 @@
         Textarea Validation Test
       </ion-label>
     </ion-item>
+    <ion-item routerLink="/standalone/validation/select-validation">
+      <ion-label>
+        Select Validation Test
+      </ion-label>
+    </ion-item>
   </ion-list>
 
   <ion-list>

packages/angular/test/base/src/app/standalone/validation/select-validation/select-validation.component.html

@@ -0,0 +1,63 @@
+<ion-header>
+  <ion-toolbar>
+    <ion-title>Select - Validation Test</ion-title>
+  </ion-toolbar>
+</ion-header>
+
+<ion-content class="ion-padding">
+  <div class="validation-info">
+    <h2>Screen Reader Testing Instructions:</h2>
+    <ol>
+      <li>Enable your screen reader (VoiceOver, NVDA, JAWS, etc.)</li>
+      <li>Tab through the form fields</li>
+      <li>When you tab away from an empty required field, the error should be announced immediately</li>
+      <li>The error text should be announced BEFORE the next field is announced</li>
+      <li>Test in Chrome, Safari, and Firefox to verify consistent behavior</li>
+    </ol>
+  </div>
+
+  <form [formGroup]="form">
+    <div class="grid">
+      <div>
+        <h2>Required Field</h2>
+        <ion-select
+          #fruitsSelect
+          id="fruits-select"
+          [label]="fieldMetadata.fruits.label"
+          placeholder="Select one"
+          interface="alert"
+          [helperText]="fieldMetadata.fruits.helperText"
+          [errorText]="fieldMetadata.fruits.errorText"
+          formControlName="fruits"
+          required
+        >
+          <ion-select-option value="apples">Apples</ion-select-option>
+          <ion-select-option value="oranges">Oranges</ion-select-option>
+          <ion-select-option value="pears">Pears</ion-select-option>
+        </ion-select>
+      </div>
+
+      <div>
+        <h2>Optional Field (No Validation)</h2>
+        <ion-select
+          #optionalSelect
+          id="optional-select"
+          [label]="fieldMetadata.optional.label"
+          placeholder="Select one"
+          interface="alert"
+          [helperText]="fieldMetadata.optional.helperText"
+          formControlName="optional"
+        >
+          <ion-select-option value="red">Red</ion-select-option>
+          <ion-select-option value="blue">Blue</ion-select-option>
+          <ion-select-option value="green">Green</ion-select-option>
+        </ion-select>
+      </div>
+    </div>
+  </form>
+
+  <div class="ion-padding">
+    <ion-button id="submit-btn" expand="block" [disabled]="form.invalid" (click)="onSubmit()">Submit Form</ion-button>
+    <ion-button id="reset-btn" expand="block" fill="outline" (click)="form.reset()">Reset Form</ion-button>
+  </div>
+</ion-content>

packages/angular/test/base/src/app/standalone/validation/select-validation/select-validation.component.scss

@@ -0,0 +1,36 @@
+.grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
+  grid-row-gap: 20px;
+  grid-column-gap: 20px;
+}
+
+h2 {
+  font-size: 12px;
+  font-weight: normal;
+  color: var(--ion-color-step-600);
+  margin-top: 10px;
+  margin-bottom: 5px;
+}
+
+.validation-info {
+  margin: 20px;
+  padding: 10px;
+  background: var(--ion-color-light);
+  border-radius: 4px;
+}
+
+.validation-info h2 {
+  font-size: 14px;
+  font-weight: 600;
+  margin-bottom: 10px;
+}
+
+.validation-info ol {
+  margin: 0;
+  padding-left: 20px;
+}
+
+.validation-info li {
+  margin-bottom: 5px;
+}

packages/angular/test/base/src/app/standalone/validation/select-validation/select-validation.component.ts

@@ -0,0 +1,63 @@
+import { CommonModule } from '@angular/common';
+import { Component } from '@angular/core';
+import {
+  FormBuilder,
+  ReactiveFormsModule,
+  Validators
+} from '@angular/forms';
+import {
+  IonButton,
+  IonContent,
+  IonHeader,
+  IonSelect,
+  IonSelectOption,
+  IonTitle,
+  IonToolbar
+} from '@ionic/angular/standalone';
+
+@Component({
+  selector: 'app-select-validation',
+  templateUrl: './select-validation.component.html',
+  styleUrls: ['./select-validation.component.scss'],
+  standalone: true,
+  imports: [
+    CommonModule,
+    ReactiveFormsModule,
+    IonSelect,
+    IonSelectOption,
+    IonButton,
+    IonHeader,
+    IonToolbar,
+    IonTitle,
+    IonContent
+  ]
+})
+export class SelectValidationComponent {
+  // Field metadata for labels and error messages
+  fieldMetadata = {
+    fruits: {
+      label: 'Fruits',
+      helperText: "Select an option",
+      errorText: 'This field is required'
+    },
+    optional: {
+      label: 'Colors',
+      helperText: 'You can skip this field',
+      errorText: ''
+    }
+  };
+
+  form = this.fb.group({
+    fruits: ['', Validators.required],
+    optional: ['']
+  });
+
+  constructor(private fb: FormBuilder) {}
+
+  // Submit form
+  onSubmit(): void {
+    if (this.form.valid) {
+      alert('Form submitted successfully!');
+    }
+  }
+}