feat(01-foundation-01): monorepo scaffolding, Docker Compose, and shared data models

- pyproject.toml: uv workspace with 5 member packages (shared, gateway, router, orchestrator, llm-pool)
- docker-compose.yml: PostgreSQL 16 + Redis 7 + Ollama services on konstruct-net
- .env.example: all required env vars documented, konstruct_app role (not superuser)
- scripts/init-db.sh: creates konstruct_app role at DB init time
- packages/shared/shared/config.py: Pydantic Settings loading all env vars
- packages/shared/shared/models/message.py: KonstructMessage, ChannelType, SenderInfo, MessageContent
- packages/shared/shared/models/tenant.py: Tenant, Agent, ChannelConnection SQLAlchemy 2.0 models
- packages/shared/shared/models/auth.py: PortalUser model for admin portal auth
- packages/shared/shared/db.py: async SQLAlchemy engine, session factory, get_session dependency
- packages/shared/shared/rls.py: current_tenant_id ContextVar and configure_rls_hook with parameterized SET LOCAL
- packages/shared/shared/redis_keys.py: tenant-namespaced key constructors (rate_limit, idempotency, session, engaged_thread)

docker-compose.yml

@@ -0,0 +1,66 @@
+version: "3.9"
+
+networks:
+  konstruct-net:
+    driver: bridge
+
+volumes:
+  postgres_data:
+  redis_data:
+  ollama_data:
+
+services:
+  postgres:
+    image: postgres:16-alpine
+    container_name: konstruct-postgres
+    environment:
+      POSTGRES_DB: konstruct
+      POSTGRES_USER: postgres
+      POSTGRES_PASSWORD: postgres_dev
+    volumes:
+      - postgres_data:/var/lib/postgresql/data
+      - ./scripts/init-db.sh:/docker-entrypoint-initdb.d/init-db.sh:ro
+    ports:
+      - "5432:5432"
+    networks:
+      - konstruct-net
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U postgres -d konstruct"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  redis:
+    image: redis:7-alpine
+    container_name: konstruct-redis
+    command: redis-server --save 60 1 --loglevel warning
+    volumes:
+      - redis_data:/data
+    ports:
+      - "6379:6379"
+    networks:
+      - konstruct-net
+    healthcheck:
+      test: ["CMD", "redis-cli", "ping"]
+      interval: 5s
+      timeout: 5s
+      retries: 10
+
+  ollama:
+    image: ollama/ollama:latest
+    container_name: konstruct-ollama
+    volumes:
+      - ollama_data:/root/.ollama
+    ports:
+      - "11434:11434"
+    networks:
+      - konstruct-net
+    deploy:
+      resources:
+        reservations:
+          devices:
+            - driver: nvidia
+              count: all
+              capabilities: [gpu]
+    # Service starts even if no GPU is available — GPU config is optional
+    restart: unless-stopped