Feat: SwapQuoterV2

[ChiTimesChi]

Description

Supersedes #249. Adds new Quoter contract, which is supposed to keep track of all the supported chain pools. Pools could be either:

• Used for "origin swap" only in the bridge workflow.
• Be a whitelisted liquidity pool for a bridge token, and thus be used either for "origin swaps", or for "destination swaps" from the given bridge token.

In both cases, the pools could be of two types:

• Default Pool. Implement IDefaultPool interface. In other words, these are the pools that Synapse:Bridge currently works with. Allows a single-hop swap between a set of tokens.
• Linked Pool. New wrapper for multiple liquidity pools (which could be both default and non-default pools). Allows multi-hop swaps between a set of tokens.

Quoter returns SynapseRouter-compatible SwapQuery structs, which define the swap parameters. See #257 for more details about Router<>Quoter internal interactions.

TODO:

• Adjust old Quoter tests to use QuoterV2 instead.
• Make SynapseRouter address to be upgradeable by the contract owner.
• Add parity tests where both LinkedPool and SwapQuoterV2 are used.
• Add unit tests for Swap Quoter V2.
  • Fix found bugs(?)

Checklist

• New Contracts have been tested
• Lint has been run
• I have checked my code and corrected any misspellings

[github-actions]

Pull Request Test Coverage Report for Build 5762213519

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-1.8%) to 13.861%

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Totals
Change from base Build 5752621076:	-1.8%
Covered Lines:	664
Relevant Lines:	4356

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💛 - Coveralls

[ChiTimesChi]

Parity tests where both LinkedPool and SwapQuoterV2 would've caught bug fixed in bd99d2f, therefore added these tests to the TODO list.

Shouldn't be too hard, though the old test structure is likely to be these as messy as other parity tests out there.

[mikeyrf]

@ChiTimesChi outside of a few questions above, looks good to me.

[ChiTimesChi]

@mikeyrf the set of tests should be completed now