Fix harness stress regressions

[jayscambler]

Summary

• Add scenario-family/new-scenario ergonomics, drift analytics, and iterative investigation support for the harness stress work.
• Wire solve/provider/judge/lifecycle hook coverage through production solve paths.
• Bound Python Pi/Pi-RPC solve role calls by generation budget, including per-role overrides, and expose solve family metadata in JSON/status output.
• Harden TS schema-evolution designer parsing for Pi-style JSON with fences, prose, comments, trailing commas, and camelCase fields.
• Address reviewer follow-up: close one-shot budgeted runtime clients, lazy-resolve iterative investigate architect runtime, and report solve run-end generation counts separately from improvement rounds.

Linear

Closes AC-686, AC-688, AC-689, AC-690, AC-691, AC-692, AC-693.

Verification

• uv run --frozen ruff check src tests/test_knowledge_solver.py tests/test_per_role_provider.py tests/test_cli_investigate.py tests/test_cli_simulate_runtime.py tests/test_rlm_competitor.py
• uv run --frozen mypy src
• uv run --frozen pytest -> 6000 passed, 42 skipped
• npm run lint
• npx vitest run tests/schema-evolution-designer-parsing.test.ts tests/agent-task-pipeline.test.ts tests/spec-auto-heal.test.ts -> 94 passed

Notes

• Full npm test was attempted before this reviewer patch. It still fails on unrelated existing TS CLI timeout tests and Python cross-runtime venv/uv races, plus the pre-existing TS type-assertion budget baseline. Targeted TS parser/family tests and TS typecheck pass.

[linear]

AC-686 RubricDriftMonitor: add dimension-level drift detection from generations.dimension_summary_json

AC-688 Expose family-specific scenario generation pipelines via `autoctx new-scenario --family <name>`

AC-689 `autoctx investigate` is scenario-gen + synthetic executor — does not drive a long LLM session, blocking compaction-stress tests

AC-690 `autoctx solve` does not honor `AUTOCONTEXT_EXTENSIONS` — extension hooks never fire on the solve path

AC-691 Regression: Python Pi solve does not enforce generation-time-budget on long role calls

AC-692 Regression: TypeScript Pi schema-evolution creation should recover from invalid JSON responses

AC-693 Regression: Python solve JSON omits resolved scenario family metadata