add calc_bonds_given_shares_and_rate to rust utils

[dpaiton]

Adds a Rust version of the solidity calculateInitialBondReserves function in HyperdriveMath.sol.

[github-actions]

Hyperdrive Gas Benchmark

Benchmark suite	Current: d21d7a6	Previous: fc0d2bf	Deviation	Status
addLiquidity: min	733 gas	733 gas	0%	🟰
addLiquidity: avg	56856 gas	56917 gas	-0.1072%	✅
addLiquidity: max	97520 gas	97572 gas	-0.0533%	✅
checkpoint: min	558 gas	536 gas	4.1045%	🚨
checkpoint: avg	30358 gas	30360 gas	-0.0066%	✅
checkpoint: max	79983 gas	79983 gas	0%	🟰
closeLong: min	755 gas	733 gas	3.0014%	🚨
closeLong: avg	23312 gas	23235 gas	0.3314%	🚨
closeLong: max	105204 gas	106259 gas	-0.9929%	✅
closeShort: min	802 gas	802 gas	0%	🟰
closeShort: avg	24730 gas	24985 gas	-1.0206%	✅
closeShort: max	105555 gas	105686 gas	-0.1240%	✅
initialize: min	662 gas	662 gas	0%	🟰
initialize: avg	161026 gas	161053 gas	-0.0168%	✅
initialize: max	234375 gas	234375 gas	0%	🟰
openLong: min	757 gas	735 gas	2.9932%	🚨
openLong: avg	55966 gas	56019 gas	-0.0946%	✅
openLong: max	225599 gas	225577 gas	0.0098%	🚨
openShort: min	712 gas	690 gas	3.1884%	🚨
openShort: avg	56654 gas	56589 gas	0.1149%	🚨
openShort: max	220880 gas	220946 gas	-0.0299%	✅
removeLiquidity: min	777 gas	755 gas	2.9139%	🚨
removeLiquidity: avg	76758 gas	76726 gas	0.0417%	🚨
removeLiquidity: max	184507 gas	184551 gas	-0.0238%	✅

This comment was automatically generated by workflow using github-action-benchmark.

[coveralls]

coverage: 97.107% (-0.1%) from 97.203% when pulling d21d7a6 on dpaiton/add-calc-bonds into 3b0ae37 on main.