feat: Add PSM pocket change (SC-724)

[lucas-manuel]

Updates to:

• Account for balance of USDC in pocket for totalAssets() accounting
• Transfer assets in and out of the pocket for deposit/withdraw/swaps
• Add an invariant test suite to set the pocket and maintain accounting
• Add additional test coverage for different pocket scenarios
• Add coverage to demonstrate breaking accounting (Start with PSM as default, get deposits, transfer pocket to another address, check totalAssets - this saw a drop in totalAssets before fix)
• Update testing to use a non-psm pocket by default

[github-actions]

Coverage after merging sc-724-psm-pocket-change into master will be

100.00%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
deploy
PSM3Deploy.sol	100%	100%	100%	100%
src
PSM3.sol	100%	100%	100%	100%

[hexonaut]

LGTM. Very thorough.