feat: APIv2 endpoints for Arbitrum messages and batches

[akolotov]

Motivation

This PR is continuation of work to support Arbitrum related entities in the BlockScout and depends on the changes introduced in #9312. It implements new API endpoints:

• api/v2/arbitrum/batches: Provides minimal details about all batches.
• api/v2/arbitrum/batches/{batch_number}: Offers complete details about a specific batch.
• api/v2/arbitrum/batches/count: Returns the number of indexed batches.
• api/v2/arbitrum/messages/to-rollup: Provides details about all L1-to-L2 messages.
• api/v2/arbitrum/messages/to-rollup/count: Returns the number of L1-to-L2 messages.
• api/v2/arbitrum/messages/from-rollup: Provides details about all L2-to-L1 messages.
• api/v2/arbitrum/messages/from-rollup/count: Returns the number of L2-to-L1 messages.
• api/v2/blocks/arbitrum-batch/{batch_number}: Allows retrieval of all blocks included in a batch.
• api/v2/transactions/arbitrum-batch/{batch_number}: Allows retrieval of all transactions included in a batch.
• api/v2/main-page/arbitrum/messages/to-rollup: Provides details about the latest 6 relayed L1-to-L2 messages.
• api/v2/main-page/arbitrum/batches/latest-number: Returns the latest sealed batch number.
• api/v2/main-page/arbitrum/batches/committed: Provides minimal details about the latest 10 committed batches.

The api/v2/transactions/{tx_hash} endpoint has been extended to include a "arbitrum" element, offering additional information about associated batches and cross-chain messages:

"arbitrum": {
  "batch_number": 30480,
  "commitment_transaction": {
    "hash": "0x7a0e9c700fec6bb4d1950c725e2093692ac67f9dc3bc3cfb84aa21a9cdbfd3e7",
    "status": "finalized",
    "timestamp": "2024-04-18T22:19:46.000000Z"
  },
  "confirmation_transaction": {
    "hash": "0x0f5c71ec4abf0d25235e47dd47009c5b89d9c87a28fde124533883af4b60657a",
    "status": "finalized",
    "timestamp": "2024-04-18T22:28:28.000000Z"
  },
  "contains_message": null,
  "status": "Confirmed on base"
}

and the /api/v2/blocks/{block_number} endpoint has been extended with the following element:

"arbitrum": {
  "batch_number": null,
  "commitment_transaction": {
    "hash": null,
    "status": null,
    "timestamp": null
  },
  "confirmation_transaction": {
    "hash": null,
    "status": null,
    "timestamp": null
  },
  "status": "Processed on rollup"
 }

Changelog

Enhancements

• Implemented a new controller BlockScoutWeb.API.V2.ArbitrumController.
• Implemented a new view BlockScoutWeb.API.V2.ArbitrumView.
• Changes in the controllers BlockScoutWeb.API.V2.BlockController and BlockScoutWeb.API.V2.TransactionController are made to allow getting items included in a batch.
• Explorer.Chain.Arbitrum.Reader has been extended with the functions to read corresponding items from the database.

Checklist for your Pull Request (PR)

• If I added new functionality, I added tests covering it.
• If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.
• I checked whether I should update the docs and did so by submitting a PR to https://github.com/blockscout/docs
• If I added/changed/removed ENV var, I submitted a PR to https://github.com/blockscout/docs to update the list of env vars at https://github.com/blockscout/docs/blob/master/for-developers/information-and-settings/env-variables.md and I updated the version to master in the Version column. Changes will be reflected in this table: https://docs.blockscout.com/for-developers/information-and-settings/env-variables.
• If I added new DB indices, I checked, that they are not redundant with PGHero or other tools.
• If I added/removed chain type, I modified the Github CI matrix and PR labels accordingly.

[varasev]

Just a minor suggestion: maybe rename originating to origination for these fields to unify naming

[akolotov]

Addressed in f4d1ce7