Handler overhaul

[AnsonYeung]

There is some further optimization in mind including optimizing the states and there is some regression since I do not include the code for detecting whether there is any call rn. Once the state optimization is included I believe this will be resolved anyway.

I also want to remove resumeValue and instead have the runtime modify the saved locals directly as that seem to cause quite some amount of excessive code.

The current approach mandates the use of the lifter. As lifter can not handle semantics of handle blocks (and it does not need to), we lower handle block to an equivalent form first, without the insertion of effect checks/resumption prelude. Now we invoke the lifter after handle block is translated and before the actual instrumentation takes place. We make use of the fact that lifter will preserve the mayRaiseEffect field.

For stack safety, I simplified the approach taken in #307, since we always include the entry state and we do not need to split into different cases when stack safety is enabled.