Normalize P2WPKH scripts in merged mining weight computation

During V35→V36 transition, miners using bech32/P2WPKH LTC addresses had
their raw SegWit scriptPubKey (0014{hash20}) used as weight keys in DOGE
PPLNS. DOGE does not support SegWit — this produced invalid address keys.

Normalize weight keys in all 4 merged mining paths:
- compute_merged_payout_hash (consensus commitment)
- V36-only merged weights skiplist (ensure_v36_skiplist)
- Per-chain merged skiplist V35 branch (ensure_merged_skiplist)
- Per-chain merged skiplist V36 Tier 2 fallback

P2WPKH (22b) → P2PKH conversion, P2PKH/P2SH passthrough,
P2TR/P2WSH skipped (unconvertible). Share data unchanged on wire.

Also adds chain_h and best share hash to FORK-DIAG logging for
chain depth divergence diagnostics.

Author: frstrtr

src/impl/ltc/node.cpp

@@ -1533,7 +1533,13 @@ void NodeImpl::clean_tracker()
                      << " gap=" << (chain.size() - verified.size())
                      << " best_h=" << (m_best_share_hash.IsNull() ? 0
                          : (verified.contains(m_best_share_hash)
-                            ? verified.get_height(m_best_share_hash) : -1));
+                            ? verified.get_height(m_best_share_hash) : -1))
+                     << " chain_h=" << (m_best_share_hash.IsNull() ? 0
+                         : (chain.contains(m_best_share_hash)
+                            ? chain.get_height(m_best_share_hash) : -1))
+                     << " best=" << (m_best_share_hash.IsNull()
+                         ? std::string("null")
+                         : m_best_share_hash.GetHex().substr(0, 16));
         }
     }
 }