HIP-1342: Ignore Trailing Calldata for System Contracts

[Neurone]

This PR introduces a proposal for the HIP Ignore Trailing Calldata for System Contracts.

This HIP proposes enabling system contract to accept and ignore trailing calldata beyond the ABI-defined parameters of a function. This restores EVM-parity behavior where contracts typically ignore additional bytes in calldata, allowing applications to append small "memo" or order identifiers to standard ERC-20-like calls (e.g., transfer, approve) without causing transaction failure. The change is implemented by updating the parameter decoding used by system contract so that decoding succeeds when extra bytes remain after all expected parameters are parsed. The extra bytes are ignored by the system contract and preserved in the underlying Ethereum transaction/record for off-chain consumption.

[web3-nomad]

Thank you @Neurone. I believe this will satisfy Squid's (and others) needs, and make our EVM more compatible with others

[lukelee-sl]

adding self for tracking - @lukelee-sl

[kpachhai]

I think this would be a great addition to bring HTS system contracts into being more EVM compliant.

[Ferparishuertas]

Please add @gkozyryatskyy instea Luke
thanks

[gkozyryatskyy]

After discussion within the SC team we are proposing next updates:

1. Apply Trailing Calldata to other System Contracts to ensure full, non-surprising EVM consistency across all precompiles/system contracts.
2. Remove from HIP Mitigations: paragraph.
3. Propose Show trailing data on [HashScan](https://hashscan.io/testnet/home)

Details: https://www.notion.so/swirldslabs/HIP-1342-Ignore-Trailing-CallData-for-HTS-System-Contract-2c07c9ab2591816ab313c32498854432#2c07c9ab2591816daff7cf53682a1ee7

[gkozyryatskyy]

LGTM! Thank you @Neurone !

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[codacy-production]

Up to standards ✅

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