Add best share analysis page, miner column, and UI improvements

- Best share page: hex + binary hash comparison against network target,
  per-bit coloring showing exactly which bits prevented a valid block,
  toggle between network diff at time of finding vs current diff
- Capture best share hash from ckpool logs with one-time backfill
- Persist network difficulty at time of best share for historical accuracy
- Add miner (worker) column to blocks table via coinbase address matching
- Truncate block hashes in table with full hash on hover
- Increase hashrate chart Y-axis to 7 ticks for better readability

ui/src/lib/BlocksTable.svelte

@@ -19,6 +19,26 @@
   );
 
   const currentChain = $derived(snap.data?.chain?.chain ?? "");
+
+  function truncHash(hash: string): string {
+    if (!hash || hash.length <= 16) return hash;
+    return hash.slice(0, 8) + "…" + hash.slice(-8);
+  }
+
+  function minerLabel(miner: string | undefined): string {
+    if (!miner) return "—";
+    // Show address.worker truncated
+    const dot = miner.indexOf(".");
+    if (dot < 0) {
+      // Just an address, truncate middle
+      if (miner.length > 20) return miner.slice(0, 8) + "…" + miner.slice(-6);
+      return miner;
+    }
+    const addr = miner.slice(0, dot);
+    const worker = miner.slice(dot + 1);
+    const shortAddr = addr.length > 12 ? addr.slice(0, 6) + "…" + addr.slice(-4) : addr;
+    return shortAddr + "." + worker;
+  }
 </script>
 
 <section class="card">
@@ -31,6 +51,7 @@
         <thead>
           <tr>
             <th>Height</th>
+            <th>Miner</th>
             <th>Chain</th>
             <th>Hash</th>
             <th class="num">Reward</th>
@@ -47,6 +68,7 @@
                   <span class="orphan-tag" title="Reorged out of the canonical chain at {b.orphaned_at}">orphaned</span>
                 {/if}
               </td>
+              <td class="miner-cell" title={b.miner ?? ""}>{minerLabel(b.miner)}</td>
               <td>
                 {#if b.chain && currentChain && b.chain !== currentChain}
                   <span class="chain-tag" title="Mined on {displayChain(b.chain)} - current node is on {displayChain(currentChain)}">{displayChain(b.chain)}</span>
@@ -63,8 +85,8 @@
                     href="{explorerBase}/block/{b.hash}"
                     target="_blank"
                     rel="noopener noreferrer"
-                    title="Open block on mempool.space"
-                  >{b.hash}</a>
+                    title={b.hash}
+                  >{truncHash(b.hash)}</a>
                 {:else}
                   <span class="hash mono">&mdash;</span>
                 {/if}
@@ -100,11 +122,16 @@
   .table-wrap {
     overflow-x: auto;
   }
+  .miner-cell {
+    font-size: 0.85em;
+    color: var(--fg-dim);
+    white-space: nowrap;
+    max-width: 180px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+  }
   .hash-cell {
-    /* Let the 64-char hash wrap inside the cell instead of stretching
-     * the whole table. */
-    max-width: 620px;
-    word-break: break-all;
+    white-space: nowrap;
   }
   .hash {
     color: var(--fg-dim);