feat: initial TrustOS platform scaffold

- FastAPI backend: auth, findings, dashboard, attack paths, footprint, AI translator, risk calculator, PDF report generator
- Next.js frontend: Vault dashboard, login, findings table, finding detail with AI coach, digital footprint, reports
- PostgreSQL data model: tenants, users, assets, findings, risk scores, audit reports, attack paths
- Docker Compose + Dockerfiles for all services
- Demo seed data: Acme Corp with 6 findings and 90-day risk score history
- AI Risk Translator (OpenAI/Anthropic) with plain-English business impact
- Role-based access: executive / it_admin / trustos_admin
- Scope-lock engine: authorization required before any assessment

Stage 1-8 complete: Phase 1 Vault Audit product ready

infra/Dockerfile.backend

@@ -0,0 +1,16 @@
+FROM python:3.10-slim
+
+WORKDIR /app
+
+RUN apt-get update && apt-get install -y \
+    libpango-1.0-0 libpangoft2-1.0-0 libpangocairo-1.0-0 \
+    libcairo2 libglib2.0-0 libharfbuzz0b libfontconfig1 \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt .
+RUN pip install --no-cache-dir -r requirements.txt
+
+COPY . .
+
+EXPOSE 8000
+CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8000"]