Fixes #370

Problem

When mapping INI sections to a struct with a slice of struct pointers:

type Config struct {
    Peers []*Peer `ini:"Peer,nonunique"`
}

mapToSlice calls reflect.New(typ) where typ is *Peer, creating a **Peer. Then mapToField only dereferences one level of pointer, causing a panic.

Fix

Detect when the slice element type is a pointer:

• Allocate the underlying struct type (Peer) instead of the pointer type
• Append the pointer (*Peer) to the slice instead of the struct value

Testing

All existing tests pass. Manually verified with the reproduction case from the issue:

// Before: panic: reflect: call of reflect.Value.NumField on ptr Value
// After:
// Peer 0: PublicKey=abc123 AllowedIPs=[10.0.0.1/32]
// Peer 1: PublicKey=def456 AllowedIPs=[10.0.0.2/32]