docs: add complete project documentation

- SPEC.md: project specification and goals
- ARCHITECTURE.md: system design and component descriptions
- database-schema.md: PostgreSQL schema with all tables
- implementation-plan.md: 12-phase implementation guide
- RUNNING.md: deployment and troubleshooting guide
- ORIENTATION.md: context compaction recovery guide
- README.md: project overview and quick start

Family profile: 2 adults, 2 children. Mushroom avoidance for 3/4.
Approval workflow: email proposals, one denial swaps meal.
Tech stack: FastAPI, PostgreSQL, React, Playwright, SendGrid.

.env.example

@@ -0,0 +1,23 @@
+# Database
+DATABASE_URL=postgresql://mealplanner:password@db:5432/mealplanner
+POSTGRES_PASSWORD=secure_password_here
+
+# SendGrid
+SENDGRID_API_KEY=SG.your_sendgrid_api_key
+
+# Family Emails
+FAMILY_EMAIL_1=you@example.com
+FAMILY_EMAIL_2=spouse@example.com
+RECIPES_EMAIL=you@example.com
+
+# Lucky California
+LUCKY_CA_URL=https://www.luckyncal.com
+
+# AI Image Generation (optional)
+AI_IMAGE_ENABLED=false
+AI_IMAGE_PROVIDER=openai
+AI_IMAGE_API_KEY=sk-your-api-key
+
+# Application
+LOG_LEVEL=INFO
+SECRET_KEY=change-me-to-a-random-secret-key