Implement lLTV tiers

[MerlinEgalite]

Not all LLTVs can be opened. Similarly to UniV3's fee tiers, the governance lists a set of LLTVs (that can be expended but not reduced).

[Rubilmax]

Here's how I did it:

https://github.com/morpho-labs/blue/blob/63e8da9592869a8935a4dadba3b73063db19302f/src/MarketBase.sol#L20-L21
https://github.com/morpho-labs/blue/blob/63e8da9592869a8935a4dadba3b73063db19302f/src/MarketBase.sol#L47

As noted in the comment, it could be inlined with a bunch of if/else if the tranche spacing is immutable.

[MathisGD]

https://github.com/morpho-labs/blue/blob/63e8da9592869a8935a4dadba3b73063db19302f/src/MarketBase.sol#L20-L21

I had something like that in mind.

https://github.com/morpho-labs/blue/blob/63e8da9592869a8935a4dadba3b73063db19302f/src/MarketBase.sol#L47

So you check it for each interaction ? Isn't it more efficient to list markets, and then to check a slot that you would need to read in any case for each interaction.

As noted in the comment, it could be inlined with a bunch of if/else if the tranche spacing is immutable.

It will very probably not be, but good point yes.

[Rubilmax]

So you check it for each interaction ? Isn't it more efficient to list markets, and then to check a slot that you would need to read in any case for each interaction.

Indeed, adding a boolean flag to the storage to specific liquidationLtvs upon market creation would be cleaner and probably cheaper

[MerlinEgalite]

Related to this discussion, and I'm for adding this into the createMarket function to remove gas overhead for users