fix: clone util should clone symbol properties of object (#1258)

The `clone` function only iterated over string-keyed properties via
`for...in`, missing symbol properties entirely.

### Changes
- Added `Object.getOwnPropertySymbols()` iteration to clone symbol-keyed
properties
- Added test case for nested symbol property cloning

### Example
```typescript
const sym = Symbol('test')
const obj = { a: 1, [sym]: { b: 2 } }
const cloned = clone(obj)

// Before: cloned[sym] was undefined
// After: cloned[sym] equals { b: 2 } (deep cloned)
```

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<details>

<summary>Original prompt</summary>

> clone util should clone symbol properties of object
> 
>   if (isObject(value)) {
>     const result: Record<PropertyKey, unknown> = {}
> 
>     for (const key in value) {
>       result[key] = clone(value[key])
>     }
> 
>     return result as any
>   }


</details>



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Co-authored-by: unnoq <64189902+unnoq@users.noreply.github.com>

Author: Copilot

packages/shared/src/object.test.ts

@@ -85,6 +85,18 @@ it('clone', () => {
   expect(cloned.nested.arr).not.toBe(obj.nested.arr)
 })
 
+it('clone with symbol properties', () => {
+  const sym = Symbol('test')
+  const nestedSym = Symbol('nested')
+  const obj = { a: 1, [sym]: { b: 2, [nestedSym]: 3 } }
+  const cloned = clone(obj)
+
+  expect(cloned.a).toBe(1)
+  expect(cloned[sym]).toEqual({ b: 2, [nestedSym]: 3 })
+  expect(cloned[sym]).not.toBe(obj[sym])
+  expect(cloned[sym][nestedSym]).toBe(3)
+})
+
 it('get', () => {
   expect(get({ a: { b: 1 } }, ['a', 'b'])).toEqual(1)
   expect(get({ a: { b: 1 } }, ['a', 'b', 'c'])).toEqual(undefined)

packages/shared/src/object.ts

@@ -70,6 +70,10 @@ export function clone<T>(value: T): T {
       result[key] = clone(value[key])
     }
 
+    for (const sym of Object.getOwnPropertySymbols(value)) {
+      result[sym] = clone(value[sym])
+    }
+
     return result as any
   }