[GraphQL]: Add support for sysvar account parsing

[buffalojoec]

Motivation

The Solana account decoder supports parsing sysvar accounts, which means the RPC's jsonParsed encoding supports parsing of sysvar accounts. However, the GraphQL client doesn't!

Details

Simply follow the jsonParsed payload structures laid out in the account decoder here to roll custom Account types in the GraphQL schema.

You can see the existing examples for SPL Token accounts, etc. here.

• [ ] Clock
• [ ] Epoch Rewards
• [ ] Epoch Schedule
• [ ] Fees
• [ ] Last Restart Slot
• [ ] Recent Blockhashes
• [ ] Rent
• [ ] Rewards
• [ ] Slot Hashes
• [ ] Slot History
• [ ] Stake History

[github-actions[bot]]

Because there has been no activity on this issue for 7 days since it was closed, it has been automatically locked. Please open a new issue if it requires a follow up.