Runtime Fixed Size Types (Dynamic Types) support

## Brief feature description

Currently, iceoryx2 only supports transmission types with a compile time fixed size. There are already types available that support having a fixed size at runtime, but the end user API does not provide an interface to create structs containing them.

The idea would be to introduce a trait to support runtime fixed size types.

```rust
pub trait RuntimeFixedSizeTypeConfig {}

pub trait RuntimeFixedSizeType {
type Config: RuntimeFixedSizeTypeConfig;
fn required_memory_size(config: Self::Config) -> usize;
fn init(&self, allocator: ShmAllocator);
}
```

The user would implement the trait and could use it like:

```rust
let service = zero_copy::Service::new(&service_name)
.publish_subscribe()
.open_or_create::()?;

let publisher = service.publisher()
.max_dynamic_type_size(1024)
.create()?;

let sample = publisher.loan_uninit(my_dynamic_type_config)?;
sample.write_payload(...);

sample.send();
```