v0.2.1 — correct the expected burn target

v0.2.1 — correct the expected burn target

v0.2.0 pinned the chain's SubnetOwnerHotkey (5F2HTUq..., uid 161) as the
expected burn recipient. That was inferred from chain state rather than
confirmed against the provider's configuration, and it is wrong: the
provider's owner_hotkey is 5DXSBCC... (uid 229), the same key that signs
epoch results.

Effect on 0.2.0: a warning line on every burn naming a correct payload as
suspect. Weights were still submitted — the check warns rather than rejects,
so the wrong value cost a misleading log rather than a fleet-wide refusal to
submit.

No other changes. Everything in the v0.2.0 notes still applies, including the
reason to upgrade from 0.1.0.