Txgen: HighCallData GenMode uses erc20 call with 2^15 bytes calldata

[JoeHowarth]

Previously high call data txs with too low gas limit were not rejected until getting to execution, but now they are rejected at rpc. This means that we cannot fill blocks to stress proposal creation and raptor cast. This pr fixes this

The base branch was changed.

[eerkaijun]

is the execution submodule bump intended?

[omegablitz]

HighCallData also needs to require the Erc20 contract to be deployed

[Copilot]

Pull Request Overview

This PR refactors the HighCallData generator to use ERC20 contract calls with large calldata (2^15 bytes) instead of deployment transactions. The change addresses an issue where transactions with insufficient gas limits are now rejected at the RPC level rather than during execution, requiring a new approach to stress-test block filling, proposal creation, and raptor cast.

Key changes:

• Removed the HighCallDataLowGasLimit generation mode entirely
• Modified HighCallData generator to use ERC20 contract calls with 2KB calldata instead of deployment transactions
• Made the make_tx helper function public to support the new implementation

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
monad-eth-testutil/examples/txgen/shared/erc20.rs	Made make_tx function public for use in high calldata generation
monad-eth-testutil/examples/txgen/generators/mod.rs	Updated HighCallData generator initialization to use ERC20 contract and removed HighCallDataLowGasLimit mode
monad-eth-testutil/examples/txgen/generators/high_call_data.rs	Replaced deployment-based approach with new high_calldata_erc20_call function that creates contract calls with large calldata
monad-eth-testutil/examples/txgen/config.rs	Removed all configuration entries for deprecated HighCallDataLowGasLimit mode
monad-eth-testutil/examples/txgen/cli.rs	Removed CLI option for deprecated HighCallDataLowGasLimit mode

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[Copilot]

The bit shift operation 2 << 10 evaluates to 2048 (2 * 2^10), but the PR description states the calldata should be 2^15 bytes (32768 bytes). This should be 1 << 15 or 32768 to match the intended size.

Suggested change

	let input = vec![0u8; 2 << 10];
	let input = vec![0u8; 1 << 15];

[Copilot]

The magic number 400_000 for gas estimation is hardcoded. Consider defining this as a named constant (e.g., ESTIMATED_GAS_USAGE) to improve code clarity and maintainability.