feat: add native execution

[ra0x3]

For more context be sure to read over #389

Description

• PR does a few things:
  • Adds support for native execution
  • Cleans up the API (swapping expect and panic for ?)
  • Adds a hello-world-native example
    • Is the exact same as the hello-world example, but with native execution
  • Integrates native execution into the forc index plugin (e.g., forc index new my-index --native)
  • Updates stop index functionality to remove indices from the database as well
  • Adds some convenience index utility functions (e.g., bytes32_from_inputs)
    • Users on Discord have complained that transforming types is a PITA so that's what these functions are for
    • In the future we might break these out into a separate crate or something

Testing steps

• CI should pass
• Pull down the hello-index-native example and:
  • Run a fuel node cargo run --bin fuel-node
  • Run the example cargo run --bin hello-index-native -- --manifest examples/hello-world-native/hello_index_native.manifest.yaml
  • Trigger an event cargo run --bin hello-bin
  • Event should be indexed
• Other functionality should be unaffected
  • Should be able to upload/deploy indices
  • Should be able to stop indices

[deekerno]

Excited to see what kind of stuff this opens up.