L3 Oral Tradition: PostgreSQL persistence layer for interpretations, minority opinions, teiku

Devarim 17:9 — v'darashta v'higidu lekha et d'var hamishpat.
The inquiry requires that what is found is RECORDED.

- Ecto Repo with graceful degradation (maybe_add_repo, like other engines)
- Migration: interpretations, minority_opinions, teiku_registry tables
  - Append-only enforcement via REVOKE UPDATE/DELETE
  - Includes eish_zarah fields: coupling_trace, grounding_type, challenge_sequence
- Ecto schemas: Interpretation, MinorityOpinion, TeikuRecord
  - Changeset validations: status inclusion, panel_size > 0, grounding_type enum
  - TeikuRecord.resolve_changeset restricts updates to resolved_at/resolution only
- L3.Store bridge module: record, query, count operations
- L3 tests tagged @moduletag :l3, excluded by default (no local PostgreSQL)
  - Enable with: SHORASHIM_L3=1 mix test --include l3
- All 76 existing Elixir tests pass, 195 Prolog tests pass, 33 Haskell tests pass

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vav_pipeline/priv/repo/migrations/20260316000001_create_l3_tables.exs

@@ -0,0 +1,105 @@
+defmodule VavPipeline.Repo.Migrations.CreateL3Tables do
+  @moduledoc """
+  L3 — Oral Tradition. Three tables, append-only.
+
+  Architecture §3.7:
+    interpretations — case decisions with reasoning and Torah references
+    minority_opinions — preserved dissent (foreign key to interpretations)
+    teiku_registry — unresolvable tensions with both sides preserved
+
+  Construction §3.8 (L3 Write Protocol):
+    Every write is an INSERT. Never UPDATE. Never DELETE.
+    The application user has INSERT-only permissions.
+    Every INSERT includes shema_context_hash and processing_component.
+
+  Append-only enforcement via REVOKE is applied after table creation.
+  The shorashim_app role must be created separately (by the kohen/DBA).
+  """
+
+  use Ecto.Migration
+
+  def up do
+    # === interpretations ===
+    create table(:interpretations) do
+      add :case_ref, :text, null: false
+      add :interpretation, :text, null: false
+      add :status, :text, null: false
+      add :reasoning, :text, null: false
+      add :torah_references, {:array, :text}, null: false, default: []
+      add :roots_involved, {:array, :text}, null: false, default: []
+      add :panel_size, :integer, null: false
+      add :vote_count_for, :integer, null: false
+      add :vote_count_against, :integer, null: false
+      # Construction §3.8 additions
+      add :shema_context_hash, :text
+      add :processing_component, :text
+      # Coupling trace from eish_zarah_reading.md
+      add :coupling_trace, {:array, :text}, default: []
+
+      timestamps(type: :utc_datetime, updated_at: false)
+    end
+
+    # Status constraint
+    create constraint(:interpretations, :valid_status,
+      check: "status IN ('accepted', 'rejected', 'teiku')")
+
+    create index(:interpretations, [:case_ref])
+    create index(:interpretations, [:status])
+
+    # === minority_opinions ===
+    create table(:minority_opinions) do
+      add :interpretation_id, references(:interpretations, on_delete: :restrict), null: false
+      add :dissenting_reasoning, :text, null: false
+      add :torah_references, {:array, :text}, null: false, default: []
+      # Grounding type from eish_zarah_reading.md (achorai/panim)
+      add :grounding_type, :text
+
+      timestamps(type: :utc_datetime, updated_at: false)
+    end
+
+    create index(:minority_opinions, [:interpretation_id])
+
+    # === teiku_registry ===
+    create table(:teiku_registry) do
+      add :case_ref, :text, null: false
+      add :tension_description, :text, null: false
+      add :interpretation_a, :text, null: false
+      add :interpretation_b, :text, null: false
+      add :torah_refs_a, {:array, :text}, null: false, default: []
+      add :torah_refs_b, {:array, :text}, null: false, default: []
+      # Challenge sequence from eish_zarah_reading.md
+      add :challenge_sequence, {:array, :text}, default: []
+      # Resolution fields — teiku may be resolved later (or never)
+      add :resolved_at, :utc_datetime
+      add :resolution, :text
+
+      timestamps(type: :utc_datetime, updated_at: false)
+    end
+
+    create index(:teiku_registry, [:case_ref])
+
+    # === APPEND-ONLY ENFORCEMENT ===
+    # These execute only if the shorashim_app role exists.
+    # In dev/test, the migration runs as the superuser and these are skipped.
+    # In production, the DBA creates the role first.
+    execute """
+    DO $$
+    BEGIN
+      IF EXISTS (SELECT FROM pg_roles WHERE rolname = 'shorashim_app') THEN
+        REVOKE UPDATE, DELETE ON interpretations FROM shorashim_app;
+        REVOKE UPDATE, DELETE ON minority_opinions FROM shorashim_app;
+        REVOKE DELETE ON teiku_registry FROM shorashim_app;
+        -- teiku_registry allows UPDATE only on resolved_at and resolution
+        -- (Enforced at application level — Ecto schema validates)
+      END IF;
+    END
+    $$;
+    """
+  end
+
+  def down do
+    drop table(:teiku_registry)
+    drop table(:minority_opinions)
+    drop table(:interpretations)
+  end
+end