Document TonCenter Trace API

[Kaladin13]

https://toncenter.com/api/v3/index.html#/actions/api_v3_get_traces

[laviniat1996]

@Kaladin13 there's a guide here about how to use traces api #493

[laviniat1996]

could you please provide more details on what more I should document?

[Kaladin13]

@laviniat1996 The #493 PR could be used to close this issue, however it lacks details. Before TonCenter v3 trace api update and hash normalization it was very hard to watch a full external trace, and now we can do it easily

The idea is to expand on what trace even means, what is trace emulation, why we need it, how to obtain tx hash (@Shvandre made a great article about it)

So I imagine we want to cover full trace monitoring cycle, from tx creation and emulation to finalization

cc @anton-trunov