Fetches the list of missing Solana messages, finds the corresponding
on-chain transactions, sends an ObservationRequest to the network
and waits for consensus.
Hacky one-off script with a couple of edge cases (doesn't filter
failed txs, crashes if the boundary is not a valid tx). We can later
refactor this and add it to the find-missing-messages admin command
if we keep needing it.
commit-id:9b338dfa
Leo