[lbry] rpcserver: add ClaimTrie root hash to GetBlockTemplate()

rpcserver.go

@@ -1765,6 +1765,7 @@ func (state *gbtWorkState) blockTemplateResult(useCoinbaseValue bool, submitOld
 		Mutable:       gbtMutableFields,
 		NonceRange:    gbtNonceRange,
 		Capabilities:  gbtCapabilities,
+		ClaimTrieHash: header.ClaimTrie.String(),
 	}
 	// If the generated block template includes transactions with witness
 	// data, then include the witness commitment in the GBT result.
@@ -4663,5 +4664,8 @@ func (s *rpcServer) handleBlockchainNotification(notification *blockchain.Notifi
 
 func init() {
 	rpcHandlers = rpcHandlersBeforeInit
+	for key := range claimtrieHandlers {
+		rpcHandlers[key] = claimtrieHandlers[key]
+	}
 	rand.Seed(time.Now().UnixNano())
 }