Feat/sealed bid auction/auction on intent open

[kss-t1]

Description

Next part of Sealed Bid implementation:

• observing Intent opened onchain
• running auction for that Intent
• notifying winning Solver

Motivation and Context

How Has This Been Tested?

Types of changes (remove all unchecked types)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Style (style only changes)
• Docs
• Refactor (code that does not add new functionality nor fixes a bug)

Checklist:

• If my change requires a change to the documentation, I have updated the documentation accordingly, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.
• If my change requires additions or updates to any deployment scripts to ensure that the protocol is functional (Makefile, Dockerfile, Forge Script, etc.), I have made these changes, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.
• If my change requires additional test coverage, I have created those tests accordingly, and in either case, have checked this box to attest to my assessment of this requirement with regard to my change.

[aharvet]

Two design notes plus one not to returned data.
All good otherwise.

The base branch was changed.

[w-woloszyn]

lgtm