Use swapFeeManager as owner in mev hook

[elshan-eth]

Description

This PR changes the authorization logic for mev hook: if swapFeeManager is set, use it as owner instead of governance.

Type of change

• Bug fix
• New feature
• Breaking change
• Dependency changes
• Code refactor / cleanup
• Optimization: [ ] gas / [ ] bytecode
• Documentation or wording changes
• Other

Checklist:

• The diff is legible and has no extraneous changes
• Complex code has been commented, including external interfaces
• Tests have 100% code coverage
• The base branch is either main, or there's a description of how to merge

Issue Resolution

Closes #1300

[jubeira]

LGTM; very clean!

This pattern is starting to get used everywhere, so it makes sense to put it in SingletonAuthentication.

[jubeira]

Maybe onlySwapFeeManagerOrAuthenticate / onlySwapFeeManagerXorAuthenticate sounds a bit better (xor is what we are actually doing, although the name doesn't sound great. Leaving that to @EndymionJkb :) )

[EndymionJkb]

If we don't want to use exclusiveRole terminology, and have to make it swap-manager specific, maybe onlySwapFeeManagerOrGovernance, or onlySwapFeeManagerIfDefined?

I'd still prefer to have the _ensureAuthenticatedByExclusiveRole function parameterized by the role, and then give the modifiers more specific names, and have them call the generic role authentication (identical to VaultAdmin). It would be most consistent across the whole codebase. Otherwise we're making up different patterns and naming conventions when there's already a suitable one there.

[EndymionJkb]

Per comments on the other PR, I still suggest using a standard generic function _ensureAuthenticatedByExclusiveRole in the base contract (maybe SingletonAuthentication; wherever it makes sense), and then have either local modifiers, or if they're really all going to be swapFeeManager, the modifier could go up there, too, but separate from the generic authentication logic that just takes a "roleAddress" - in case we have something else that uses a different role later.

[EndymionJkb]

If we don't want to use exclusiveRole terminology, and have to make it swap-manager specific, maybe onlySwapFeeManagerOrGovernance, or onlySwapFeeManagerIfDefined?

I'd still prefer to have the _ensureAuthenticatedByExclusiveRole function parameterized by the role, and then give the modifiers more specific names, and have them call the generic role authentication (identical to VaultAdmin). It would be most consistent across the whole codebase. Otherwise we're making up different patterns and naming conventions when there's already a suitable one there.

[joaobrunoah]

LGTM!