feat(attribution): carry a miner's name across chains by reward preimage

Live telemetry names the miners who win often and leaves everyone else as a
hex string. Measured on mainnet: of 22 miners, 2 were named and 14 had no name
available anywhere — but 6 already had one on Planck, under the same reward
preimage. Those 6 are exactly the small operators the naming is worst for,
because a name needs a block whose first reporter the feed could separate and
they win few blocks.

The preimage is derived from a secret only its owner holds, so the same
preimage on two chains is the same operator. That is an inference the site can
stand behind, unlike guessing from timing — and it is the only lever that works
without waiting on the feed at all.

It is a separate `AttributionSource` and renders as one. `Carried` names carry
no confidence and no votes, because they assert nothing about this chain: only
that this is who the operator was last known to be. Any live attribution here
outranks one, and the row shows an `elsewhere` chip rather than the telemetry
`node` chip so the two can never be read as the same claim.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jp6a8EDar9ueEhAxzep4V5

web/src/api/generated/AttributionSource.ts

@@ -7,4 +7,4 @@
  * inference from who reported a block first, not a claim the miner made, and
  * the UI must not present the two identically.
  */
-export type AttributionSource = "preimage" | "telemetry";
+export type AttributionSource = "preimage" | "telemetry" | "carried";