[#286] Improve `ArithError` to remove impossible representation

Description

Problem: We have

-- | Denotes the error type occured in the arithmetic operation.
data ArithErrorType
  = AddOverflow
  | MulOverflow
  | SubUnderflow
  | LslOverflow
  | LsrUnderflow
  deriving stock (Show, Eq, Ord, Generic)

-- | Represents an arithmetic error of the operation.
data ArithError n m
  = MutezArithError ArithErrorType n m
  | ShiftArithError ArithErrorType n m
  deriving stock (Show, Eq, Ord, Generic)

LslOverflow and LsrUnderflow can only happen in ShiftArithError and the other three can only be part of MutezArithError. But it's not reflected in type.

Solution: Turn ArithErrorType into two types: ShiftArithErrorType and MutezArithErrorType.

Related issue(s)

Resolves #286 (closed)

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