data: refresh Oct 8 model and plan changes

[blackkcold]

Official-change refresh for 2026-10-08.

• add Claude Haiku 5.5 Low/Medium/High/XHigh/Max using current Artificial Analysis measurements
• refresh Claude Sonnet 5.5 AA task costs after Anthropic cut cache-read pricing to $0.10/M
• record new Claude Max/Team monthly Platform API credits; update Max plan notes
• record Oct 7 GPT-6 Chat rollout and updated OpenAI Pro subscription policy notes
• update README/site snapshot date and source links
• keep existing High/XHigh/Max long-agent correction rules
• recommendations remain GPT-6.1 Sol Medium (frontier value), Claude Opus 5.5 Max (absolute capability), and existing Plan categories