E3 (P1): Unify review packet construction paths

[agustif]

Parent: #206

Objective

Route all review packet construction through one canonical builder and eliminate mode drift.

Success Criteria

• prepare, run-batches, and external use the same packet-construction contract.
• Policy fields (max_files_per_batch, redacted config, narrative/next command shaping) are consistent across modes.

[agustif]

Epic status update:

Implemented on branch feat/e3-review-packet-unification in PR #228 (cd91f96).

Subtask mapping:

• E3.1: Route all review modes through canonical packet builder #219 complete in code (shared builder delegation in all three modes)
• E3.2: Remove review packet policy drift across modes #220 complete in code (policy drift removed + parity tests)
• E3.3: Delete duplicated review packet assembly logic #221 complete in code (duplicated assembly removed)

Key regression gate added:

• desloppify/tests/review/policy/test_packet_mode_parity.py

Validation run:

• pytest -q desloppify/tests/review/review_commands_cases.py desloppify/tests/review/import_scoring/test_review_external.py desloppify/tests/commands/review/test_review_process_guards_direct.py desloppify/tests/review/policy/test_packet_mode_parity.py
• Result: 103 passed.

Leaving epic open until PR #228 is merged.

[agustif]

E3 hash refresh after history cleanup:

• PR feat(e3): unify review packet construction paths #228 head is now 2858eda (force-push removed committed TASKS.md files).
• Functional E3 changes and test coverage are unchanged.

[agustif]

Completed via implementation PR(s) in this program. Closing as done.