feat: add reviewed episode promotion diagnostics

[cafitac]

Summary

• Add reviewed episode promotion support to the guarded G5 trace-candidate apply corridor.
• Add fresh-epoch metadata-gap diagnostics that identify classified legacy missing-outcome rows separately from unresolved adapter payload gaps.
• Update status/roadmap docs for the live mixed fact/procedure/episode shadow corpus checkpoint and keep default ranking migration blocked.

Test Plan

• uv run --python 3.11 pytest tests/test_cli.py::test_python_module_cli_dogfood_fresh_epoch_filters_historical_telemetry_without_mutation tests/test_cli.py::test_python_module_cli_dogfood_fresh_epoch_classifies_unknown_empty_retrieval_outcomes tests/test_cli.py::test_dogfood_trace_candidate_apply_supports_reviewed_preference_procedure_and_episode_promotions tests/test_roadmap_contract.py -q
• uv run --python 3.11 pytest tests/ -q

Live Evidence

• /Users/reddit/.agent-memory/reports/default-ranking-v0152-shadow/live-hermes-mixed-approved-50-corpus-v1-shadow.json: 50/50 pass, facts/procedures/episodes covered, zero baseline regressions, no durable ranking mutation.
• /Users/reddit/.agent-memory/reports/default-ranking-v0152-shadow/fresh-epoch-since-v0152-with-metadata-gap-diagnostic.json: still blocked on fresh-epoch coverage/metadata gap; default migration remains blocked.