chatlas 0.3.0

New features

• Chat's .tokens() method gains a values argument. Set it to "discrete" to get a result that can be summed to determine the token cost of submitting the current turns. The default ("cumulative"), remains the same (the result can be summed to determine the overall token cost of the conversation).
• Chat gains a .token_count() method to help estimate token cost of new input. (#23)

Bug fixes

• ChatOllama no longer fails when a OPENAI_API_KEY environment variable is not set.
• ChatOpenAI now correctly includes the relevant detail on ContentImageRemote() input.
• ChatGoogle now correctly logs its token_usage(). (#23)