fix(ui): head the miner panel with the best identifier, not the preimage

The panel body listed the address and preimage, but its heading still read
`0x134e73f0…df59` — the one identifier a miner does not recognise, given top
billing. It now falls back through name, address, preimage, which is the order
a reader can actually use them in.

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

web/src/components/MinerPanel.tsx

@@ -56,7 +56,15 @@ export function MinerPanel({
         <div>
           <div className="eyebrow">Miner</div>
           <h2 className="panel-title" style={{ marginTop: 4 }}>
-            {named ? row.display : shortMiner(miner)}
+            {/* The best identifier available, in the order a reader can use
+                them: an attributed node name, else the reward address the miner
+                configured, else the preimage the header carries. The full set
+                is below regardless. */}
+            {named
+              ? row.display
+              : detail?.address
+                ? `${detail.address.slice(0, 8)}…${detail.address.slice(-4)}`
+                : shortMiner(miner)}
           </h2>
           {/* All three identifiers, because they answer different questions.
               The node name is an inference and may be absent; the address is