feat(reflect): add Indirect function

Implements reflect.Indirect function to support pointer dereferencing.
This function returns the value that a pointer points to, or returns
the value unchanged if it's not a pointer.

Fixes #1354

Generated with [codeagent](https://github.com/qbox/codeagent)
Co-authored-by: luoliwoshang <luoliwoshang@users.noreply.github.com>

_cmptest/reflect_indirect/test.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"fmt"
+	"reflect"
+)
+
+func main() {
+	x := 42
+	p := &x
+
+	// Test 1: Non-pointer value - should return same value
+	v1 := reflect.Indirect(reflect.ValueOf(x))
+	fmt.Printf("Non-pointer: %v\n", v1.Interface())
+
+	// Test 2: Pointer - should dereference
+	v2 := reflect.Indirect(reflect.ValueOf(p))
+	fmt.Printf("Pointer: %v\n", v2.Interface())
+
+	// Test 3: Nil pointer
+	var nilPtr *int
+	v3 := reflect.Indirect(reflect.ValueOf(nilPtr))
+	fmt.Printf("Nil pointer valid: %v\n", v3.IsValid())
+}

runtime/internal/lib/reflect/value.go

@@ -1759,6 +1759,16 @@ func ValueOf(i any) Value {
 	return unpackEface(i)
 }
 
+// Indirect returns the value that v points to.
+// If v is a nil pointer, Indirect returns a zero Value.
+// If v is not a pointer, Indirect returns v.
+func Indirect(v Value) Value {
+	if v.Kind() != Pointer {
+		return v
+	}
+	return v.Elem()
+}
+
 // arrayAt returns the i-th element of p,
 // an array whose elements are eltSize bytes wide.
 // The array pointed at by p must have at least i+1 elements: