chore(pricing): update Anthropic model pricing constants

[jtanningbed]

Why are these changes needed?

Just a maintenance update to include anthropic newer model pricing info.

Info taken from anthropic docs

Related issue number

Checks

• I've included any doc changes needed for https://ag2ai.github.io/ag2/. See https://ag2ai.github.io/ag2/docs/Contribute#documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[jtanningbed]

before:
.venv/lib/python3.13/site-packages/autogen/oai/anthropic.py:426: UserWarning: Cost calculation not available for model claude-3-5-sonnet-20241022 warnings.warn(f"Cost calculation not available for model {model}", UserWarning)
cost={'usage_including_cached_inference': {'total_cost': 0}, 'usage_excluding_cached_inference': {'total_cost': 0}}

after:
cost={'usage_including_cached_inference': {'total_cost': 0.028481999999999997, 'claude-3-5-sonnet-20241022': {'cost': 0.002682, 'prompt_tokens': 304, 'completion_tokens': 241, 'total_tokens': 545}, 'gpt-4-0613': {'cost': 0.025799999999999997, 'prompt_tokens': 554, 'completion_tokens': 153, 'total_tokens': 707}}, 'usage_excluding_cached_inference': {'total_cost': 0.017651999999999998, 'claude-3-5-sonnet-20241022': {'cost': 0.002682, 'prompt_tokens': 244, 'completion_tokens': 130, 'total_tokens': 374}, 'gpt-4-0613': {'cost': 0.014969999999999999, 'prompt_tokens': 351, 'completion_tokens': 74, 'total_tokens': 425}}}, human_input=[])

[qingyun-wu]

Thank you @jtanningbed for your contribution! Could I have your discord id and email so that we properly acknowledge your contribution, and also have you sign CLA properly!