refactor(components): convert const to reactive where appropriate

- Inline class assignments to avoid script-level clutter
- Ignore a11y-missing-attribute instead of redundant href

src/components/TextInput/TextInput.svelte

@@ -17,34 +17,28 @@
   import WarningFilled16 from 'carbon-icons-svelte/lib/WarningFilled16';
   import { cx } from '../../lib';
 
-  const errorId = `${id}-error`;
-  const _labelClass = cx(
-    '--label',
-    hideLabel && '--visually-hidden',
-    disabled && '--label--disabled'
-  );
-  const _helperTextClass = cx('--form__helper-text', disabled && '--form__helper-text--disabled');
-  const _textInputClass = cx(
-    '--text-input',
-    light && '--text-input--light',
-    invalid && '--text-input--invalid',
-    className
-  );
+  $: errorId = `error-${id}`;
 </script>
 
 <div class={cx('--form-item', '--text-input-wrapper')} {style}>
   {#if labelText}
-    <label for={id} class={_labelClass}>{labelText}</label>
+    <label
+      for={id}
+      class={cx('--label', hideLabel && '--visually-hidden', disabled && '--label--disabled')}>
+      {labelText}
+    </label>
   {/if}
   {#if helperText}
-    <div class={_helperTextClass}>{helperText}</div>
+    <div class={cx('--form__helper-text', disabled && '--form__helper-text--disabled')}>
+      {helperText}
+    </div>
   {/if}
   <div class={cx('--text-input__field-wrapper')} data-invalid={invalid || undefined}>
     {#if invalid}
       <WarningFilled16 class={cx('--text-input__invalid-icon')} />
     {/if}
     <input
-      class={_textInputClass}
+      class={cx('--text-input', light && '--text-input--light', invalid && '--text-input--invalid', className)}
       on:click
       on:change
       on:input