Pre-seed accounts with more ETH.

This commit fixes and solves some issues around how much ETH we seed an
account with in genesis. Currently, any account that the node has keys
to sign for will be seeded with u128::MAX WEI in genesis. This also
includes the default signer account.

crates/node/src/geth.rs

@@ -84,6 +84,8 @@ impl Instance {
         for signer_address in
             <EthereumWallet as NetworkWallet<Ethereum>>::signer_addresses(&self.wallet)
         {
+            // Note, the use of the entry API here means that we only modify the entries for any
+            // account that is not in the `alloc` field of the genesis state.
             genesis
                 .alloc
                 .entry(signer_address)

crates/node/src/kitchensink.rs

@@ -131,6 +131,8 @@ impl KitchensinkNode {
             for signer_address in
                 <EthereumWallet as NetworkWallet<Ethereum>>::signer_addresses(&self.wallet)
             {
+                // Note, the use of the entry API here means that we only modify the entries for any
+                // account that is not in the `alloc` field of the genesis state.
                 genesis
                     .alloc
                     .entry(signer_address)