fix: replace isDeepStrictEqual with navigation-aware options comparison (#507)

The select cursor highlight was broken because isDeepStrictEqual in
use-select-navigation.ts and use-multi-select-state.ts would fail when
options contained identity-unstable properties (JSX label elements,
function onChange callbacks, computed disabled booleans). This caused
the reset logic to fire on every re-render, resetting focusedValue
back to the first option.

Replace isDeepStrictEqual with optionsNavigateEqual which only compares
properties that affect navigation behavior: value, disabled, and type.
ReactNode labels and function callbacks are intentionally excluded as
they are identity-unstable but don't change navigation semantics.

Fixes #472

Co-authored-by: OpenClaude Worker 3 <worker-3@openclaude.local>

src/components/CustomSelect/use-select-navigation.ts

@@ -6,10 +6,34 @@ import {
   useRef,
   useState,
 } from 'react'
-import { isDeepStrictEqual } from 'util'
 import OptionMap from './option-map.js'
 import type { OptionWithDescription } from './select.js'
 
+/**
+ * Compare two option arrays for structural equality on properties that
+ * affect navigation behavior. ReactNode `label` and function `onChange`
+ * are intentionally excluded — they are identity-unstable (new reference
+ * each render) but don't change navigation semantics.
+ */
+export function optionsNavigateEqual<T>(
+  a: OptionWithDescription<T>[],
+  b: OptionWithDescription<T>[],
+): boolean {
+  if (a.length !== b.length) return false
+  for (let i = 0; i < a.length; i++) {
+    const ao = a[i]!
+    const bo = b[i]!
+    if (
+      ao.value !== bo.value ||
+      ao.disabled !== bo.disabled ||
+      ao.type !== bo.type
+    ) {
+      return false
+    }
+  }
+  return true
+}
+
 type State<T> = {
   /**
    * Map where key is option's value and value is option's index.
@@ -524,7 +548,7 @@ export function useSelectNavigation<T>({
 
   const [lastOptions, setLastOptions] = useState(options)
 
-  if (options !== lastOptions && !isDeepStrictEqual(options, lastOptions)) {
+  if (options !== lastOptions && !optionsNavigateEqual(options, lastOptions)) {
     dispatch({
       type: 'reset',
       state: createDefaultState({