Add short::open tests

[dpaiton]

Resolved Issues

partially addresses #937

Description

This PR

• adds a few tests
• makes minor changes to error messaging, doc strings, and variable names
• moves functions from max.rs into open.rs to make them more accessible for the targeted short function (Create calculate_targeted_short hyperdrive-rs#21)

Review Checklists

Please check each item before approving the pull request. While going
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If the PR doesn't touch Solidity and/or Rust, the corresponding checklist can
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[[Reviewer Name]]

Rust

• Testing
  • Are there new or updated unit or integration tests?
  • Do the tests cover the happy paths?
  • Do the tests cover the unhappy paths?
  • Are there an adequate number of fuzz tests to ensure that we are
    covering the full input space?
  • If matching Solidity behavior, are there differential fuzz tests that
    ensure that Rust matches Solidity?

[github-actions]

Hyperdrive Gas Benchmark

Benchmark suite	Current: 612ce70	Previous: dada2f9	Deviation	Status
addLiquidity: min	33893 gas	33893 gas	0%	🟰
addLiquidity: avg	144147 gas	144301 gas	-0.1067%	✅
addLiquidity: max	428319 gas	428319 gas	0%	🟰
checkpoint: min	40220 gas	40220 gas	0%	🟰
checkpoint: avg	103888 gas	104067 gas	-0.1720%	✅
checkpoint: max	212154 gas	212154 gas	0%	🟰
closeLong: min	31517 gas	31517 gas	0%	🟰
closeLong: avg	138059 gas	137774 gas	0.2069%	🚨
closeLong: max	2640435 gas	2640435 gas	0%	🟰
closeShort: min	31394 gas	31394 gas	0%	🟰
closeShort: avg	132808 gas	132727 gas	0.0610%	🚨
closeShort: max	227565 gas	227565 gas	0%	🟰
initialize: min	31305 gas	31305 gas	0%	🟰
initialize: avg	253636 gas	253638 gas	-0.0008%	✅
initialize: max	322760 gas	322760 gas	0%	🟰
openLong: min	33437 gas	33437 gas	0%	🟰
openLong: avg	167438 gas	167331 gas	0.0639%	🚨
openLong: max	253162 gas	253162 gas	0%	🟰
openShort: min	33959 gas	33959 gas	0%	🟰
openShort: avg	170385 gas	170153 gas	0.1363%	🚨
openShort: max	385650 gas	385650 gas	0%	🟰
redeemWithdrawalShares: min	31227 gas	31227 gas	0%	🟰
redeemWithdrawalShares: avg	61837 gas	61916 gas	-0.1276%	✅
redeemWithdrawalShares: max	167572 gas	167572 gas	0%	🟰
removeLiquidity: min	31191 gas	31191 gas	0%	🟰
removeLiquidity: avg	223425 gas	223242 gas	0.0820%	🚨
removeLiquidity: max	398887 gas	398887 gas	0%	🟰

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