Add a universal epistemic protocol to default episodes

[yichen14]

Summary

• Move evaluator sufficiency into a versioned Proteus core protocol applied to every default episode, rather than a DSH-specific instruction.
• Treat external evaluators as evidence: they may fully operationalize a narrow goal or only partially cover a broad goal. The harness judges sufficiency and may evolve its own tests or evaluators when they reduce uncertainty.
• Give no-goal runs neutral phase prompts that permit open exploration and self-authored provisional goals/evaluation machinery without silently imposing an improvement objective.
• Record the protocol version in sweep manifests so runs cannot resume across changed protocol conditions; conditional wording does not reveal hidden evaluators.
• Make the adapter prompt contract and bundled DSH, Pi, Minimal, and LLM integrations consistent with the default protocol. Document Aki's frozen native-prompt path as the current legacy exception.

Scope

DSH audio evolution is the first consumer, not the owner of this behavior. A user-defined phase protocol API remains a separate follow-up; this PR changes only the universal default.

Verification

• Full Python 3.10 suite: 157 passed, 1 skipped
• Ruff: all checks passed