Add GPT-4o/GPT-4o-mini support

[tanishq-acu]

Feature description
Add GPT-4o and GPT-4o-mini models to constants in metagpt.utils.token_counter.py. Also add models to count_input_tokens() method.
Your Feature
Add "gpt-4o-mini": 128000,"gpt-4o": 128000, to metagpt.utils.token_counter.TOKEN_MAX.
Add "gpt-4o": {"prompt": 0.005, "completion": 0.015}, "gpt-4o-mini": {"prompt": 0.00015, "completion": 0.0006}, to metagpt.utils.token_counter.TOKEN_COSTS.
Can also do the same for the variants.

Also:
Add "gpt-4o", "gpt-4o-mini" to count_input_tokens in metagpt.utils.token_counter (line 335)