chore(deps): update rust-toolchain to 1.81

[Jon-Becker]

Motivation

Solution

[github-actions]

Benchmark for e729622

Click to view benchmark

Test	Base	PR	%
heimdall_cfg/complex	16.4±1.06ms	14.0±0.16ms	-14.63%
heimdall_cfg/simple	2.7±0.03ms	2.1±0.02ms	-22.22%
heimdall_decoder/seaport	44.6±2.71µs	39.8±1.32µs	-10.76%
heimdall_decoder/transfer	2.9±0.15µs	2.8±0.18µs	-3.45%
heimdall_decoder/uniswap	13.0±0.94µs	11.8±0.67µs	-9.23%
heimdall_decompiler/abi_complex	65.2±0.66ms	61.2±3.30ms	-6.13%
heimdall_decompiler/abi_simple	2.6±0.19ms	2.3±0.02ms	-11.54%
heimdall_decompiler/sol_complex	77.8±0.98ms	75.7±1.48ms	-2.70%
heimdall_decompiler/sol_simple	3.0±0.04ms	2.9±0.04ms	-3.33%
heimdall_decompiler/yul_complex	72.6±3.22ms	66.3±2.39ms	-8.68%
heimdall_decompiler/yul_simple	2.8±0.21ms	2.6±0.02ms	-7.14%
heimdall_disassembler/complex	1036.9±61.69µs	990.1±28.63µs	-4.51%
heimdall_disassembler/simple	53.6±7.17µs	48.6±3.20µs	-9.33%
heimdall_vm/erc20_transfer	426.9±36.84µs	350.0±6.53µs	-18.01%
heimdall_vm/fib	1200.3±33.09µs	944.5±23.45µs	-21.31%
heimdall_vm/ten_thousand_hashes	5.1±0.15s	5.2±0.16s	+1.96%