Separate out parameters of createMerkleInstant function

[smol-ninja]

As discussed in #1 (comment):

• Add separate shared parameters struct for createMerkleLL and createMerkleLT functions. Then DRY'ify their internal logic.
• Separate out the parameters of createMerkleInstant function and remove its dependency from the current ConstructorParams struct.
• Remove ConstructorParams struct.

The objective is to separate out createMerkleInstant input parameters from createMerkleLL and createMerkleLT. Right now, there are a tons of parameters shared between createMerkleLL and createMerkleLT which can be DRY'ified through a common struct between them. However, due to them sharing it with createMerkleInstant, its not possible.