fix: route info segment overrides not updating in dev overlay

@@ -24,6 +24,7 @@ const createSegmentNode = ({ }  describe('Segment Explorer', () => {+  let act: typeof import('@testing-library/react').act   let cleanup: typeof import('@testing-library/react').cleanup   let renderHook: typeof import('@testing-library/react').renderHook   let useSegmentTree: typeof SegmentExplorer.useSegmentTree@@ -42,6 +43,7 @@ describe('Segment Explorer', () => {     const rtl = require('@testing-library/react/pure')     renderHook = rtl.renderHook     cleanup = rtl.cleanup+    act = rtl.act   })    afterEach(() => {@@ -154,9 +156,11 @@ describe('Segment Explorer', () => {       value: undefined,     }) -    removeSegmentNode(-      createSegmentNode({ pagePath: '/constructor/page.js', type: 'page' })-    )+    act(() => {+      removeSegmentNode(+        createSegmentNode({ pagePath: '/constructor/page.js', type: 'page' })+      )+    })      expect(result.current).toEqual({       children: {@@ -274,9 +278,11 @@ describe('Segment Explorer', () => {       value: undefined,     }) -    removeSegmentNode(-      createSegmentNode({ pagePath: '/a/b/layout.js', type: 'layout' })-    )+    act(() => {+      removeSegmentNode(+        createSegmentNode({ pagePath: '/a/b/layout.js', type: 'layout' })+      )+    })      expect(result.current).toEqual({       children: {@@ -340,4 +346,38 @@ describe('Segment Explorer', () => {       value: undefined,     })   })++  test('gives changed nodes a new identity so consumers can memoize on them', () => {+    insertSegmentNode(+      createSegmentNode({ pagePath: '/a/layout.js', type: 'layout' })+    )++    const { result } = renderHook(useSegmentTree)++    // `pagePath` splits on '/', so the leading slash produces an empty segment.+    const rootBefore = result.current+    const aBefore = rootBefore.children['']!.children['a']!++    act(() => {+      insertSegmentNode(+        createSegmentNode({ pagePath: '/a/page.js', type: 'page' })+      )+    })++    const rootAfter = result.current+    const aAfter = rootAfter.children['']!.children['a']!++    // Consumers memoize on `node.children`, so every node along the mutated+    // path must be a fresh object. Reusing them would leave newly inserted+    // segments invisible until the consumer remounted.+    expect(rootAfter).not.toBe(rootBefore)+    expect(rootAfter.children).not.toBe(rootBefore.children)+    expect(aAfter).not.toBe(aBefore)+    expect(aAfter.children).not.toBe(aBefore.children)+    expect(Object.keys(aAfter.children)).toEqual(['layout.js', 'page.js'])++    // Untouched subtrees stay shared, and the previous snapshot is not mutated.+    expect(Object.keys(aBefore.children)).toEqual(['layout.js'])+    expect(aAfter.children['layout.js']).toBe(aBefore.children['layout.js'])+  }) })

@@ -75,55 +75,81 @@ function createTrie<Value = string>({     }   } -  function insert(value: Value) {-    let currentNode = root-    const segments = getCharacters(value)+  function copyChildren(children: TrieNode<Value>['children']) {+    return Object.assign(Object.create(null), children)+  } +  // Snapshots must be immutable for `useSyncExternalStore` consumers, so+  // updates copy the nodes along the mutated path instead of mutating them+  // in place. Untouched subtrees stay shared.+  function copyPath(segments: string[]): TrieNode<Value>[] {+    const newRoot: TrieNode<Value> = {+      value: root.value,+      children: copyChildren(root.children),+    }++    const path: TrieNode<Value>[] = [newRoot]+    let currentNode = newRoot     for (const segment of segments) {-      if (!currentNode.children[segment]) {-        currentNode.children[segment] = {-          value: undefined,-          // Skip value for intermediate nodes-          children: Object.create(null),-        }+      const existingNode = currentNode.children[segment]+      const copiedNode: TrieNode<Value> = {+        value: existingNode?.value,+        children: existingNode+          ? copyChildren(existingNode.children)+          : Object.create(null),       }-      currentNode = currentNode.children[segment]+      currentNode.children[segment] = copiedNode+      currentNode = copiedNode+      path.push(copiedNode)     } -    currentNode.value = value+    return path+  } -    root = { ...root }+  function insert(value: Value) {+    const segments = getCharacters(value)+    const path = copyPath(segments)++    path[path.length - 1].value = value++    root = path[0]     markUpdated()   }    function remove(value: Value) {-    let currentNode = root     const segments = getCharacters(value) -    const stack: TrieNode<Value>[] = []-    let found = true+    // Locate the node first, so a miss doesn't copy or notify.+    let currentNode = root     for (const segment of segments) {-      if (!currentNode.children[segment]) {-        found = false-        break+      const childNode = currentNode.children[segment]+      if (!childNode) {+        return       }-      stack.push(currentNode)-      currentNode = currentNode.children[segment]!+      currentNode = childNode     }     // If the value is not found, skip removal-    if (!found || !compare(currentNode.value, value)) {+    if (!compare(currentNode.value, value)) {       return     }-    currentNode.value = undefined-    for (let i = stack.length - 1; i >= 0; i--) {-      const parentNode = stack[i]++    const path = copyPath(segments)+    path[path.length - 1].value = undefined++    // Prune nodes that no longer hold a value or any children.+    for (let i = segments.length - 1; i >= 0; i--) {+      const parentNode = path[i]       const segment = segments[i]-      if (Object.keys(parentNode.children[segment]!.children).length === 0) {+      const childNode = parentNode.children[segment]!+      if (+        childNode.value === undefined &&+        Object.keys(childNode.children).length === 0+      ) {         delete parentNode.children[segment]       }     } -    root = { ...root }+    root = path[0]     markUpdated()   }