Both the `Error` and `Result` fields on `RPCRes` had `omitempty` tags, so null results were being swallowed. We didn't catch this in integration tests because JavaScript tolerates missing keys. This is now fixed by using a custom JSON marshaler.

Fixes #2049

l2geth: Add commands to initialize from a URL, and dump the current chainstate

This PR adds two commands to l2geth:

- `geth init <url> <genesisHash>`, which will download a remote genesis JSON file, compare its hash to the one specified on the CLI, then reinitialize the chain config.
- `geth dump-chain-cfg`, which will dump the current chain config to stdout.

These commands will make it easier for us to adopt the upcoming gas schedule hardfork.

Fixes: ENG-1906

integration-tests: Changes to make it work with live networks again

chore(deps): bump trim-off-newlines from 1.0.1 to 1.0.3

l2geth: fix monotonicity logging bug

feat: add confirmation depth awareness to txmgr

go/proxyd: Cache block-dependent RPCs

test: use hardhat-ethers for importing factories in integration tests

go/proxyd: Add integration tests and batch support

- Fixes ENG-1903

Split OVMMulticall.sol into Multicall.sol & OVMContext.sol in integration tests

The logline `Blocknumber monotonicity violation`
was being logged erroneously. This commit ensures
that it is not logged when it doesn't need to be
logged.

It would previously log if the L1 blocknumber
was equal to or less than and now it only logs
if the L1 blocknumber is less than.

Bumps [trim-off-newlines](https://github.com/stevemao/trim-off-newlines) from 1.0.1 to 1.0.3.
- [Release notes](https://github.com/stevemao/trim-off-newlines/releases)
- [Commits](https://github.com/stevemao/trim-off-newlines/compare/v1.0.1...v1.0.3)

---
updated-dependencies:
- dependency-name: trim-off-newlines
  dependency-type: indirect
...
Signed-off-by: dependabot[bot] <support@github.com>

Version Packages

Develop -> Master PR

chore: add changeset for l2geth

Add missing changeset for https://github.com/ethereum-optimism/optimism/pull/2011

A replica can be configured with the flag
`--sequencer.clienthttp` or the env var
`SEQUENCER_CLIENT_HTTP` which points to the
sequencer and when users hit the RPC endpoint
`eth_sendRawTransaction` it will forward the
value to the sequencer.

If running a mainnet node, this value should be
set to `https://mainnet.optimism.io` or an
infrastructure provider such as Quiknode, Infura
or Alchemy.