refactor: move reflect.Indirect test to _demo and use panic()

- Moved test from _cmptest/reflect_indirect/ to _demo/go/reflect-indirect/
- Refactored to use panic() for validation instead of fmt.Println
- Added proper assertions for all test cases

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

_cmptest/reflect_indirect/test.go

@@ -1,24 +0,0 @@
-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())
-}