Update README to start nodes from contract deployed block

ops/deployments-from-scratch.md

@@ -201,6 +201,15 @@
   # }
   ```
 
+* Get the start block for Nitro Adjudicator events by executing the following command:
+
+  ```bash
+  laconic-so deployment --dir nitro-contracts-deployment exec nitro-contracts "jq '.receipt.blockNumber' /app/deployment/hardhat-deployments/geth/NitroAdjudicator.json"
+
+  # Expected output:
+  101
+  ```
+
 * Switch to `testnet-ops/nitro-bridge-setup` directory on your local machine:
 
   ```bash
@@ -230,6 +239,9 @@
   na_address: ""
   vpa_address: ""
   ca_address: ""
+
+  # Specifies the block number to start looking for nitro adjudicator events
+  nitro_chain_start_block: 0
   ```
 
 * Update the target dir in `setup-vars.yml`:
@@ -313,6 +325,8 @@
   export L1_BRIDGE_MULTIADDR="/dns4/bridge.laconic.com/tcp/3005/p2p/$BRIDGE_PEER_ID"
   export L2_BRIDGE_MULTIADDR="/dns4/bridge.laconic.com/tcp/3006/p2p/$BRIDGE_PEER_ID"
 
+  export NITRO_CHAIN_START_BLOCK=$(laconic-so deployment --dir nitro-contracts-deployment exec nitro-contracts "jq '.receipt.blockNumber' /app/deployment/hardhat-deployments/geth/NitroAdjudicator.json")
+
   # Create the required config file
   cat <<EOF > nitro-node-config.yml
   nitro_chain_url: "wss://sepolia.laconic.com"
@@ -320,6 +334,7 @@
   ca_address: "$CA_ADDRESS"
   vpa_address: "$VPA_ADDRESS"
   asset_address: "${ASSET_ADDRESS}"
+  nitro_chain_start_block: $NITRO_CHAIN_START_BLOCK
   bridge_nitro_address: "$BRIDGE_NITRO_ADDRESS"
   nitro_l1_bridge_multiaddr: "$L1_BRIDGE_MULTIADDR"
   nitro_l2_bridge_multiaddr: "$L2_BRIDGE_MULTIADDR"

testnet-nitro-node.md

@@ -36,6 +36,7 @@
   # ca_address: ""
   # vpa_address: ""
   # asset_address: ""
+  # nitro_chain_start_block: 0
   # bridge_nitro_address: ""
   # nitro_l1_bridge_multiaddr: ""
   # nitro_l2_bridge_multiaddr: ""