feat: add private Phase 8 grouped rewrite

[binaryaaron]

Summary

Add the private graph-profile implementation of SDK Phase 8 Grouped Rewrite. A grouped operation now produces one complete keyed group result or fails as a group, with exact evaluation/repair accounting, Phase 4 release qualification, capability checkpoints, and cleanup evidence.

This is stacked on the P8 intake branch from #253. It does not implement RFC Phase 9 Result Compatibility and does not expose Grouped Rewrite through the public API.

Design

• Declare and admit explicit private rewrite groups as an exact target partition with bounded atomic-group refinement.
• Consume only authenticated, release-qualified Phase 7 Substitute baselines.
• Analyze, rewrite, evaluate, repair, and re-evaluate complete groups; prohibit partial-key and independent-row fallback.
• Route every DataDesigner execution through NddAdapter.run_workflow() with exact model roles and typed compile/open/per-dispatch/close capability snapshots.
• Attribute provider failures through private attempt bindings rather than trusting public record IDs.
• Close every declared operation stage, apply frozen failure precedence, and use the existing Phase 4 ledger as the sole dependency/atomic publication authority.
• Retire candidate-bearing authority before reduction, then require sealed pre- and post-reduction cleanup attestations before release.

Compatibility and non-goals

Public Rewrite remains on its existing legacy/combined path. Redact, Annotate, Hash, Substitute, run/preview/evaluate behavior, result types, CLI, docs, and the bundled skill are unchanged.

This PR does not start Result Compatibility, inspection, independent runtime, durable state, or production Intake/OpenShell work.

Validation

• make format-check
• make typecheck
• focused Phase 8/private-wiring matrix: 389 passed
• make test: 4,675 passed, 11 skipped
• make coverage: 4,675 passed, 11 skipped; 90% total coverage
• independent finite oracle: 167 canonical traces and 910 events
• mutation evidence: 15/15 oracle mutants and 17/17 production-seam mutants killed
• make build-wheel plus clean-environment inventory/import/resource/public-boundary checks
• independent review-only workflow: accepted with zero findings; all six host validations passed
• CI: Check and full coverage on Python 3.11, 3.12, and 3.13 passed
• signed candidate: 614e1f4104e107a673864eb7a2e12de5e49607f0

Full implementation and review evidence: #257 (comment)

DCO correction and exact-head evidence: #257 (comment)

Final CI evidence: #257 (comment)

CI run: https://github.com/NVIDIA-NeMo/Anonymizer/actions/runs/33866860829

P8 evidence: #257 (comment)

Reviewer path

Start with the frozen contract and admission model, then review the NDD capability/wire boundary, group operation ledger, Phase 4 release/cleanup service, and finally the independent reference and mutation suites.

This PR must remain draft. Do not mark #253 or this PR ready, and do not merge either PR without a separate operator approval.