Reduce the playable word list and randomize the word of the day

[EthanJantz]

Currently, the Semantle game will pull a word from the full vocabulary of the Word2Vec model. This isn't in line with the original game, which uses a list of popular words as the playable word list. Shortening the word list for this solver would (probably) improve performance.

• Change the Semantle class to select a random word from a word list defined in the repository
• Constrain the word list to a list of popular words