Add State overrides to eth_call

[maxencerb]

What

The goal of this PR is to add state overrides to call and eth_call EIP1193 types. These overrides are helpful in many cases. It modifies the state of selected accounts before the transaction. It is a default feature in geth. It allows to modify:

• The balance of the account
• The code on a given account
• The state (key-value mapping representation of the storage) either on top of the account storage or completely override it.

Why

I only added the rpc schema and changed the "low-level" call function. But the first case scenario that comes in mind is the approve and swap transaction simulation.

If you know the mapping key for the allowances, you could change the allowance to the max allowance before a simulateContract call. This would allow a cheap onchain simulation of the rates you could get.

const { result } = await publicClient.simulateContract({
  address: '0xFBA3912Ca04dd458c843e2EE08967fC04f3579c2',
  abi: mangroveABI,
  functionName: 'marketOrderByTick',
  account,
  stateOverride: {
    // modify the state of the USDT contract
    [USDT_ADDRESS]: {
      // Allows to modify storage while keeping other storage intact
      stateDiff: {
        // modify the storage slot corresponding to allowance
        [userAllowanceSlot]: "0xffffffffff...",
      }
    }
  }
})

---

PR-Codex overview

Focus of this PR:

This PR focuses on adding the stateOverride property to various functions (call, simulateContract, readContract, and multicall) and introducing related types and error classes.

Detailed summary:

• Added stateOverride property to call, simulateContract, readContract, and multicall functions.
• Added StateOverride type defining state overrides for eth_call method.
• Added InvalidBytesLengthErrorType and InvalidBytesLengthError classes.
• Added RpcStateOverride and RpcStateMapping types.
• Added StateMapping and StateOverride types.
• Added AccountStateConflictErrorType, AccountStateConflictError, StateAssignmentConflictErrorType, and StateAssignmentConflictError classes.
• Updated various files with the new changes.

The following files were skipped due to too many changes: src/errors/stateOverride.ts, src/actions/public/multicall.test.ts, site/pages/docs/actions/public/call.md, src/actions/public/call.ts, site/pages/docs/contract/simulateContract.md, src/actions/public/call.test.ts

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[changeset-bot]

🦋 Changeset detected

Latest commit: 99ce411

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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[vercel]

@maxencerb is attempting to deploy a commit to the wevm Team on Vercel.

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[jxom]

Seems chill. Just a couple of comments!

[maxencerb]

I made some changes, added tests for readContract, multicall, and call, added some error handling.

Also added API docs on simulateContract, readContract, multicall, and call and added a usage example on simulateContract.

[jxom]

It's looking good! If we can get coverage on these lines, then I'm happy to merge!

Test coverage cmd: bun run test:cov public/call.test

[maxencerb]

I added coverage to these lines on call.test.ts.