WIP: Convex frxETH/WETH strategy - copy of BaseCurveStrategy & ConvexStrategy

[naddison36]

There are two implementations of the new Convex frxETH/WETH strategy

1. This one clones BaseCurveStrategy to BaseTwoAssetCurveStrategy and ConvexStrategy to ConvexTwoAssetStrategy
2. The other uses a library to abstract whether the Curve pool has two or three coins. Convex frxETH/WETH strategy #1846

If you made a contract change, make sure to complete the checklist below before merging it in master.

Refer to our documentation for more details about contract security best practices.

Contract change checklist:

• Code reviewed by 2 reviewers.
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• Unit tests pass
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[github-actions]

	Warnings
⚠️	👀 This PR needs at least 2 reviewers

Generated by 🚫 dangerJS against 51f9c41

[sparrowDom]

BaseCurveStrategy scales the amount by the asset decimals. Should be done here as well I think: https://github.com/OriginProtocol/origin-dollar/pull/1842/files#diff-b64fd0bec03db7ed6bb2701ecb172041e4f1764412109f6def228fab87fed611R48

[naddison36]

BaseCurveStrategy has to scale USDT and USDC up to 18 decimals to match DAI and the Curve pool LP token.
For the ETH-based Curve pools, all the assets are 18 decimals so they don't need scaling up.
I commented on the contract that the strategy can only be used if all the assets and LP token have the same decimals.
This might get added back if I can make BaseCurveStrategy handle Curve pools with either 2 or 3 assets.

[sparrowDom]

thanks that makes sense

[notion-workspace]

Development of new Convex strategy that supports only 2 Curve pool assets

[naddison36]

Closing this in preference to PR #1846