feat: initial scaffold — MVP catalogue de données d'API

- Backend NestJS : CRUD api_entries + categories, upload YAML multi-fichiers,
  génération docs AsyncAPI (@asyncapi/cli@6.0.0) et OpenAPI (redocly)
- Fix: route wildcard GET /api/apis/:id/*path pour servir les assets statiques
  (CSS/JS) générés par AsyncAPI HTML template (contournement bug path-to-regexp v8)
- Frontend Angular 19 : pages catalog, browse, api-detail, doc-viewer, upload (DSFR)
- Seeder de données de démo (idempotent)
- Docker Compose dev + Dockerfiles + manifests K8s
- Documentation : README, architecture, référence API REST

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

infra/k8s/backend.yaml

@@ -0,0 +1,83 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: backend
+  namespace: datacat
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: backend
+  template:
+    metadata:
+      labels:
+        app: backend
+    spec:
+      containers:
+        - name: backend
+          image: git.chmod777.dev/z3n/datacat/back:latest
+          ports:
+            - containerPort: 3000
+          env:
+            - name: NODE_ENV
+              value: production
+            - name: PORT
+              value: "3000"
+            - name: DATABASE_HOST
+              value: postgres
+            - name: DATABASE_PORT
+              value: "5432"
+            - name: DATABASE_NAME
+              value: datacat
+            - name: DATABASE_USER
+              valueFrom:
+                secretKeyRef:
+                  name: datacat-secrets
+                  key: db-user
+            - name: DATABASE_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: datacat-secrets
+                  key: db-password
+            - name: DOCS_OUTPUT_DIR
+              value: /app/docs-output
+          volumeMounts:
+            - name: docs-output
+              mountPath: /app/docs-output
+          resources:
+            requests:
+              memory: "256Mi"
+              cpu: "100m"
+            limits:
+              memory: "512Mi"
+              cpu: "500m"
+          livenessProbe:
+            httpGet:
+              path: /health
+              port: 3000
+            initialDelaySeconds: 15
+            periodSeconds: 20
+          readinessProbe:
+            httpGet:
+              path: /health
+              port: 3000
+            initialDelaySeconds: 5
+            periodSeconds: 10
+      volumes:
+        - name: docs-output
+          persistentVolumeClaim:
+            claimName: datacat-docs-pvc
+      imagePullSecrets:
+        - name: registry-secret
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: backend
+  namespace: datacat
+spec:
+  selector:
+    app: backend
+  ports:
+    - port: 80
+      targetPort: 3000