PR-003A: PostgreSQL Repository Adapters + Persistence Independence Test

- 4 PostgreSQL adapter stubs (Session, Mission, DecisionCase, Artifact)
- Migration 001: Initial schema (sessions, missions, artifacts, decision_cases)
- Persistence Independence Test: 6 tests verifying same behavior
  across InMemory and PostgreSQL implementations
- ADR-008: PostgreSQL Adapters for Production
- ADR-009: Persistence Independence

Architecture Quality Gates:
- Domain unchanged
- Application unchanged
- Only adapter implementation changes
- Same test suite runs against both implementations

Next: PR-003B — Schema & Migrations, PR-003C — Integration Tests,
PR-003D — Unit of Work / Transactions

packages/infrastructure/migrations/001_initial_schema.sql

@@ -0,0 +1,96 @@
+-- Migration 001: Initial Schema
+-- 
+-- Domain model mapped to PostgreSQL tables.
+-- Domain does NOT know about this schema.
+-- Schema is infrastructure concern.
+
+-- Sessions
+CREATE TABLE IF NOT EXISTS field_sessions (
+  id VARCHAR(32) PRIMARY KEY,
+  location_lat DECIMAL(10, 8) NOT NULL,
+  location_lng DECIMAL(11, 8) NOT NULL,
+  location_accuracy DECIMAL(10, 2),
+  date DATE NOT NULL,
+  status VARCHAR(20) NOT NULL DEFAULT 'planned',
+  mission_ids TEXT[] DEFAULT '{}',
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+-- Missions
+CREATE TABLE IF NOT EXISTS missions (
+  id VARCHAR(32) PRIMARY KEY,
+  session_id VARCHAR(32) NOT NULL REFERENCES field_sessions(id),
+  location_lat DECIMAL(10, 8) NOT NULL,
+  location_lng DECIMAL(11, 8) NOT NULL,
+  location_accuracy DECIMAL(10, 2),
+  status VARCHAR(20) NOT NULL DEFAULT 'created',
+  device_model VARCHAR(100) NOT NULL,
+  device_os VARCHAR(100) NOT NULL,
+  device_app_version VARCHAR(50) NOT NULL,
+  artifact_ids TEXT[] DEFAULT '{}',
+  observation_ids TEXT[] DEFAULT '{}',
+  sequence_number INTEGER NOT NULL DEFAULT 1,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+-- Artifacts
+CREATE TABLE IF NOT EXISTS artifacts (
+  id VARCHAR(32) PRIMARY KEY,
+  type VARCHAR(50) NOT NULL,
+  version_major INTEGER NOT NULL DEFAULT 1,
+  version_minor INTEGER NOT NULL DEFAULT 0,
+  version_patch INTEGER NOT NULL DEFAULT 0,
+  hash_algorithm VARCHAR(20) NOT NULL DEFAULT 'sha256',
+  hash_value VARCHAR(64) NOT NULL,
+  created_by VARCHAR(100) NOT NULL,
+  storage_protocol VARCHAR(20) NOT NULL,
+  storage_bucket VARCHAR(200),
+  storage_path TEXT NOT NULL,
+  parent_id VARCHAR(32) REFERENCES artifacts(id),
+  lineage TEXT[] DEFAULT '{}',
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+-- Decision Cases
+CREATE TABLE IF NOT EXISTS decision_cases (
+  id VARCHAR(32) PRIMARY KEY,
+  mission_id VARCHAR(32) NOT NULL REFERENCES missions(id),
+  title VARCHAR(500) NOT NULL,
+  description TEXT NOT NULL,
+  priority VARCHAR(20) NOT NULL,
+  confidence VARCHAR(20) NOT NULL,
+  recommended_action TEXT NOT NULL,
+  observation_ids TEXT[] DEFAULT '{}',
+  evidence_ids TEXT[] DEFAULT '{}',
+  finding_id VARCHAR(32) NOT NULL,
+  decision_id VARCHAR(32) NOT NULL,
+  review_id VARCHAR(32) NOT NULL,
+  status VARCHAR(20) NOT NULL DEFAULT 'pending',
+  version INTEGER NOT NULL DEFAULT 1,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+-- Indexes for common queries
+CREATE INDEX IF NOT EXISTS idx_missions_session_id ON missions(session_id);
+CREATE INDEX IF NOT EXISTS idx_missions_status ON missions(status);
+CREATE INDEX IF NOT EXISTS idx_decision_cases_mission_id ON decision_cases(mission_id);
+CREATE INDEX IF NOT EXISTS idx_decision_cases_status ON decision_cases(status);
+CREATE INDEX IF NOT EXISTS idx_field_sessions_date ON field_sessions(date);
+CREATE INDEX IF NOT EXISTS idx_field_sessions_status ON field_sessions(status);
+
+-- Update trigger for updated_at
+CREATE OR REPLACE FUNCTION update_updated_at_column()
+RETURNS TRIGGER AS $$
+BEGIN
+  NEW.updated_at = NOW();
+  RETURN NEW;
+END;
+$$ language 'plpgsql';
+
+CREATE TRIGGER update_field_sessions_updated_at BEFORE UPDATE ON field_sessions
+  FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();
+
+CREATE TRIGGER update_missions_updated_at BEFORE UPDATE ON missions
+  FOR EACH ROW EXECUTE FUNCTION update_updated_at_column();