enhancement: update fuel explorer

[ra0x3]

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Description

• PR does a few things:
  • Prevent usage of reserved names in GraphQL schema object names
  • Refactors the fuel-indexer-types module
    • Import structure was spaghetti 🍝
  • Removes namespacing types in codgen
    • We just import the types w/o a namespace, and use the reserved keyword check
  • Adds the initial implementation of Header, Block, and Conensus
    • I've left notes, as this work is a WIP.
      • It cannot be put on a feature branch because master needs some of these changes
  • Removes the explorer_indexer example
    • Now that we have our actual explorer, we don't need this
  • Updates tests accordingly
  • Adds custom indexer-specific HeaderData, and Genesis types
    • We need these until fuel_core_client types don't compile to WASM #286 is finished

Testing steps

• CI should pass
• Rebuild your modules
• Start the service connected to beta-3 using the fuel-explorer indexer

cargo run --bin fuel-indexer -- run --manifest examples/fuel-explorer/fuel-explorer/fuel_explorer.manifest.yaml --run-migrations --fuel-node-host beta-3.fuel.network --fuel-node-port 80

• Open your GraphQL playground http://localhost:29987/api/playground/fuel/explorer
• Query for the initial block data

query {
  block {
    block_id
    header {
      block_id
      da_height
      transactions_count
      message_receipt_count
      transactions_root
      message_receipt_root
      height
      prev_root
      timestamp
      application_hash
    }
    consensus {
      label
      poa
      unknown
      genesis
    }
  }
}

Changelog

• enhancement: update fuel explorer with initial type implementations

[deekerno]

Did a first pass and everything looks pretty good. Left some comments; I'll approve once they're addressed/resolved.