fix(eds-core-react, eds-utils)!: Improve onChange handler typing for TextField component and remove multiline support (#4134)

* feat(eds-core-react): export the Textarea component
* feat(eds-core-react): make Textarea isolated and supporting all props
* chore(eds-core-react): mock React.useId for consistent snapshot IDs in tests
* feat(eds-utils)!: remove custom useId
* feat(eds-utils)!: update useAutoResize to return a callback ref
* feat(eds-utils): enhance OverridableComponent type to include HTML attributes for better flexibility

Author: Copilot

.cursorrules

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+# Cursor AI Instructions for Equinor Design System
+
+Follow all guidelines from `.github/copilot-instructions.md`

CODEMOD.md

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+# Codemod for TextField multiline to Textarea Migration
+
+This codemod helps automate the migration from `TextField` with `multiline` prop to the `Textarea` component.
+
+## Prerequisites
+
+- Node.js 14 or higher
+- jscodeshift installed globally or as a dev dependency
+
+```bash
+npm install -g jscodeshift
+# or
+pnpm add -D jscodeshift
+```
+
+## Usage
+
+### Quick Start
+
+```bash
+# Run on a single file
+npx jscodeshift -t textfield-to-textarea.codemod.js src/components/MyComponent.tsx
+
+# Run on a directory
+npx jscodeshift -t textfield-to-textarea.codemod.js src/
+
+# With TypeScript parser
+npx jscodeshift -t textfield-to-textarea.codemod.js --parser=tsx src/
+```
+
+### Options
+
+```bash
+# Dry run (see what would change without modifying files)
+npx jscodeshift -t textfield-to-textarea.codemod.js --dry src/
+
+# Show diff
+npx jscodeshift -t textfield-to-textarea.codemod.js --print src/
+
+# Verbose output
+npx jscodeshift -t textfield-to-textarea.codemod.js -v 2 src/
+```
+
+## What the Codemod Does
+
+1. **Finds TextField components** with `multiline` prop set to `true`
+2. **Replaces component name** from `TextField` to `Textarea`
+3. **Removes multiline prop**
+4. **Renames textareaRef to ref** (if present)
+5. **Updates imports** to include `Textarea` instead of (or in addition to) `TextField`
+6. **Removes TextField import** if no longer used in the file
+
+## Examples
+
+### Example 1: Basic Transformation
+
+**Before:**
+```tsx
+import { TextField } from '@equinor/eds-core-react'
+
+function MyComponent() {
+  return (
+    <TextField 
+      multiline 
+      label="Description"
+      placeholder="Enter text"
+    />
+  )
+}
+```
+
+**After:**
+```tsx
+import { Textarea } from '@equinor/eds-core-react'
+
+function MyComponent() {
+  return (
+    <Textarea 
+      label="Description"
+      placeholder="Enter text"
+    />
+  )
+}
+```
+
+### Example 2: With Refs
+
+**Before:**
+```tsx
+import { TextField } from '@equinor/eds-core-react'
+import { useRef } from 'react'
+
+function MyComponent() {
+  const ref = useRef<HTMLTextAreaElement>(null)
+  
+  return (
+    <TextField 
+      multiline 
+      textareaRef={ref}
+      label="Notes"
+    />
+  )
+}
+```
+
+**After:**
+```tsx
+import { Textarea } from '@equinor/eds-core-react'
+import { useRef } from 'react'
+
+function MyComponent() {
+  const ref = useRef<HTMLTextAreaElement>(null)
+  
+  return (
+    <Textarea 
+      ref={ref}
+      label="Notes"
+    />
+  )
+}
+```
+
+### Example 3: Mixed Usage (TextField kept for single-line)
+
+**Before:**
+```tsx
+import { TextField } from '@equinor/eds-core-react'
+
+function MyComponent() {
+  return (
+    <>
+      <TextField label="Name" />
+      <TextField multiline label="Description" />
+    </>
+  )
+}
+```
+
+**After:**
+```tsx
+import { TextField, Textarea } from '@equinor/eds-core-react'
+
+function MyComponent() {
+  return (
+    <>
+      <TextField label="Name" />
+      <Textarea label="Description" />
+    </>
+  )
+}
+```
+
+## Limitations
+
+The codemod handles most common cases but has limitations:
+
+### Not Handled Automatically
+
+1. **Conditional multiline prop:**
+   ```tsx
+   <TextField multiline={someCondition} />
+   ```
+   → Manual review needed
+
+2. **Dynamic prop spreading:**
+   ```tsx
+   const props = { multiline: true, label: "Text" }
+   <TextField {...props} />
+   ```
+   → Manual review needed
+
+3. **Props not available on Textarea:**
+   ```tsx
+   <TextField multiline inputIcon={<Icon />} />
+   ```
+   → Manual refactoring needed (remove inputIcon)
+
+4. **Complex ref patterns:**
+   ```tsx
+   <TextField multiline ref={combineRefs(ref1, ref2)} />
+   ```
+   → Manual review needed
+
+## Manual Review Checklist
+
+After running the codemod, review the following:
+
+- [ ] Check for TextField components with conditional `multiline` props
+- [ ] Verify all Textarea components have correct props
+- [ ] Remove any Textarea-incompatible props (inputIcon, unit, meta)
+- [ ] Update TypeScript types if using TextFieldProps
+- [ ] Test all migrated components
+- [ ] Update tests if they reference TextField with multiline
+- [ ] Check console for any warnings
+
+## Prompts for Common Scenarios
+
+### Find all TextField with multiline in your codebase
+
+```bash
+# Using grep
+grep -r "TextField.*multiline" src/
+
+# Using ripgrep (faster)
+rg "TextField.*multiline" src/
+
+# Using ag (the silver searcher)
+ag "TextField.*multiline" src/
+```
+
+### Find potential missed cases
+
+```bash
+# Find TextField with multiline spread in props
+rg "TextField.*\{\.\.\..*\}" src/
+
+# Find conditional multiline
+rg "multiline=\{" src/
+```
+
+## Testing the Codemod
+
+Test the codemod on sample files before running on your entire codebase:
+
+```bash
+# Create a test file
+cat > test-file.tsx << 'EOF'
+import { TextField } from '@equinor/eds-core-react'
+
+export const TestComponent = () => (
+  <TextField multiline label="Test" />
+)
+EOF
+
+# Run codemod
+npx jscodeshift -t textfield-to-textarea.codemod.js --dry test-file.tsx
+
+# Check the output
+cat test-file.tsx
+```
+
+## Rollback
+
+If you need to rollback the changes:
+
+```bash
+# If you have git
+git checkout -- src/
+
+# If you made a backup
+cp -r src.backup/* src/
+```
+
+## Support
+
+If you encounter issues with the codemod:
+
+1. Check the limitations section above
+2. Review the manual review checklist
+3. Try running with `-v 2` for verbose output
+4. Create an issue with a minimal reproduction case
+
+## Advanced Usage
+
+### Custom Parser Options
+
+```bash
+# For JavaScript files
+npx jscodeshift -t textfield-to-textarea.codemod.js --parser=babylon src/
+
+# For Flow
+npx jscodeshift -t textfield-to-textarea.codemod.js --parser=flow src/
+```
+
+### Ignore Patterns
+
+```bash
+# Ignore specific directories
+npx jscodeshift -t textfield-to-textarea.codemod.js \
+  --ignore-pattern="**/node_modules/**" \
+  --ignore-pattern="**/build/**" \
+  src/
+```
+
+### Process Specific File Types
+
+```bash
+# Only .tsx files
+find src -name "*.tsx" -exec npx jscodeshift -t textfield-to-textarea.codemod.js {} \;
+
+# Both .tsx and .ts files
+npx jscodeshift -t textfield-to-textarea.codemod.js \
+  --extensions=tsx,ts \
+  src/
+```