feat: experimental encoding for contracts, scripts and predicates

[hal3e]

closes: #1278, #1279, #1046

This PR adds support for the new encoding scheme for contracts, scripts and predicates.

I have added a new ExperimentalBoundedEncoder which can be activated with the experimental cfg flag.
I have tried to minimize the impact of the new encoder as much as possible to make it easier for review. A full refactor of the whole sdk is necessary once the new encoding becomes the default one.

• The function selector changed and now it is the name of the method.
• The CALL opcode changed with the new encoding and is expecting the following call data: ContractID, pointer to fn_selector (name of the method), pointer to encoded arguments, number of coins, asset_id, gas_forwarded.

To run the tests, first install forc: 0.52.0 and build the projects with:
forc build --path packages/fuels --experimental-new-encoding then run the tests with:
cargo test --all-targets --workspace --features experimental

Checklist

• I have linked to any relevant issues.
• I have added tests that prove my fix is effective or that my feature works.
• I have added necessary labels.
• I have done my best to ensure that my PR adheres to the Fuel Labs Code Review Standards.
• I have requested a review from the relevant team or maintainers.

[MujkicA]

Great work! Thanks for the effort you put into making this PR easily digestible.
The new encoding will make things a lot simpler on our side, looking forward to making it stable.

[segfault-magnet]

Excellent work. Especially with the feature-gating, removing the old encoding is looking to be painless.

[digorithm]

Excellent work @hal3e!