Add Kubernetes configuration for Firecrawl deployment

Added new files for setting up Firecrawl on a Kubernetes Cluster. The files include Kubernetes manifests for deploying API, worker, playwright service, and Redis with associated ConfigMap and Secret associated resources. Also, updated the self-host documentation to include instructions for Kubernetes deployment.

examples/k8n/worker.yaml

@@ -0,0 +1,24 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: worker
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: worker
+  template:
+    metadata:
+      labels:
+        app: worker
+    spec:
+      imagePullSecrets:
+        - name: docker-registry-secret
+      containers:
+      - name: worker
+        image: ghcr.io/winkk-dev/firecrawl:latest
+        envFrom:
+        - configMapRef:
+            name: firecrawl-config
+        - secretRef:
+            name: firecrawl-secret