Re-gate found 'max' still reached provider adapters that reject/mis-handle it on
lanes beyond openai-codex/native: direct openai + openai-api + azure-foundry
GPT-5 (APIs top out at xhigh), and Azure-Foundry/Bedrock-hosted LEGACY Claude
(the pre-adaptive classifier only matched native Anthropic provider names, so max
survived to the 8k manual-thinking budget). Extended the GPT-5/o-series ceiling
to all OpenAI-family lanes and the pre-adaptive-Claude ceiling to azure/bedrock/
vertex lanes (gated on 'claude' in the model id so non-Claude models on those
lanes are untouched). Regression tests for both lanes.