feat: add extra withdrawal request for pre-funding

[LouisTsai-Csie]

This is based on PR #144 , but based on devnets/bal/6 branch.

Features:
Add 15K pre-funding account via injecting withdrawal request only in funding block. commit 15ad8f6 ensures the request only happens in funding, not gas bumping phase.

The funding account starting from this private key with 15K accounts.

# Deterministic sender pool of 15K accounts.
# Funded via system contract withdrawals (funding.txt) in payload generation.
# Placed outside pre-allocation to ensure accounts remain uncached.
SENDER_BASE_KEY = (
    0x1111111111111111111111111111111111111111111111111111111111111111
)

In the last commit, i drop the combination of compute benchmark on perf-devnet-3, confirmed by Maria