Given a list of strings, find all strings that encode to the same value using a Caesar Cipher. (A Caesar Cipher rotates characters, e.g. in CC3: a->d, b->e, ..., z->c)

To group strings by their Caesar cipher encoding, first create a helper function that normalizes each string. This function should shift all characters in a string so that the first character becomes 'a'. You can achieve this by calculating the difference between the first character's ASCII value and 'a', and then applying this shift to all other characters using the modulo operator to wrap around the alphabet.

Next, iterate through the input list of strings. For each string, compute its normalized form using the helper function. Use a hash map (or dictionary) where the keys are the normalized strings and the values are lists of the original strings that map to that normalized form.

Finally, iterate through the values (which are lists of original strings) of this hash map. Each list represents a group of strings that are Caesar cipher equivalents. Return these lists as the result.