Add Drizzle + Postgres setup (task 03)

drizzle-orm + postgres driver + drizzle-kit wired up. Core schema declares
users, households, and household_members. docker-compose.dev.yaml runs
Postgres 16 locally. Initial migration generated and verified applied.

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

docker-compose.dev.yaml

@@ -0,0 +1,15 @@
+services:
+  famapp-db:
+    image: postgres:16-alpine
+    restart: unless-stopped
+    environment:
+      POSTGRES_DB: famapp
+      POSTGRES_USER: famapp
+      POSTGRES_PASSWORD: famapp
+    ports:
+      - "5432:5432"
+    volumes:
+      - famapp-db-data:/var/lib/postgresql/data
+
+volumes:
+  famapp-db-data: