- Add RoleFn<T>, AdapterFn, AdapterBinding types to workflow-protocol
- Mark AgentFn, AgentFnResult, AgentBinding as @deprecated
- Refactor createWorkflow to accept AdapterBinding instead of AgentBinding
- Adapter returns typed meta directly — no more extract call in workflow loop
- Add buildThreadInput (ThreadContext-based), keep buildAgentPrompt as deprecated wrapper
- Update template bundle-entries to wrap AgentFn as AdapterFn
- Update solve-issue tests to use AdapterFn directly