Check if WasmGenerator::create_call_stack_local needs more behaviors

[Acaccia]

Until recently, the method WasmGenerator::create_call_stack_local could allocate enough space for:

1. representing a Value in memory as it is represented on the Wasm stack,
2. representing a complete Value in memory,
3. or both.

However, this commit changed the behavior of point 2. It fixed an issue where a Value which contains an in-memory type would only have enough space for (offset, length). Now it also allocates length space to write the in-memory Values.

This fixes bugs for functions like map-get?, which couldn't write the entirety of the result in memory due to a lack of allocated space.
However, this allocates more memory than before, which might not be needed for some other functions.

We should check if the old behavior is enough for some functions and if yes, add a way to use it from WasmGenerator::create_call_stack_local.