feat: add Valkey as k8s sidecar for Redis compatibility

- Add Valkey 8.0 alpine container as sidecar in k8s deployment
- Configure with appropriate security context (non-root, no privilege escalation)
- Add resource limits (256Mi memory, 200m CPU) and requests (128Mi, 50m)
- Add health probes using valkey-cli ping command
- Configure Redis connection via REDIS_HOST and REDIS_PORT environment variables
- Add Redis config to runtime.exs, dev.exs, and test.exs
- Valkey runs on localhost:6379 within the same pod as Phoenix app

config/dev.exs

@@ -92,5 +92,10 @@ config :towerops, ToweropsWeb.Endpoint,
     ]
   ]
 
+# Configure Redis/Valkey for development
+config :towerops, :redis,
+  host: "localhost",
+  port: 6379
+
 # Enable dev routes for dashboard and mailbox
 config :towerops, dev_routes: true

config/runtime.exs

@@ -46,6 +46,10 @@ if config_env() == :prod do
 
   host = System.get_env("PHX_HOST") || "example.com"
 
+  # Configure Redis/Valkey connection
+  redis_host = System.get_env("REDIS_HOST") || "localhost"
+  redis_port = String.to_integer(System.get_env("REDIS_PORT") || "6379")
+
   config :libcluster,
     topologies: [
       k8s: [
@@ -147,4 +151,8 @@ if config_env() == :prod do
 
   # Set default sender for all emails
   config :towerops, :mailer_from, {"Towerops", "hi@towerops.net"}
+
+  config :towerops, :redis,
+    host: redis_host,
+    port: redis_port
 end

config/test.exs

@@ -46,6 +46,11 @@ config :towerops, ToweropsWeb.Endpoint,
 # Set environment identifier for runtime checks
 config :towerops, :env, :test
 
+# Configure Redis/Valkey for testing
+config :towerops, :redis,
+  host: "localhost",
+  port: 6379
+
 # Use mocks for testing
 config :towerops,
   ping_module: Towerops.Monitoring.PingMock,

k8s/deployment.yaml

@@ -84,6 +84,10 @@ spec:
                 secretKeyRef:
                   name: towerops-secrets
                   key: SECRET_KEY_BASE
+            - name: REDIS_HOST
+              value: "localhost"
+            - name: REDIS_PORT
+              value: "6379"
           envFrom:
             - secretRef:
                 name: towerops-db
@@ -113,3 +117,44 @@ spec:
             timeoutSeconds: 2
             successThreshold: 1
             failureThreshold: 2
+        - name: valkey
+          image: valkey/valkey:8.0-alpine
+          imagePullPolicy: IfNotPresent
+          securityContext:
+            allowPrivilegeEscalation: false
+            runAsNonRoot: true
+            runAsUser: 999
+            capabilities:
+              drop:
+                - ALL
+            seccompProfile:
+              type: RuntimeDefault
+          ports:
+            - containerPort: 6379
+              name: valkey
+          resources:
+            requests:
+              memory: "128Mi"
+              cpu: "50m"
+            limits:
+              memory: "256Mi"
+              cpu: "200m"
+          livenessProbe:
+            exec:
+              command:
+                - valkey-cli
+                - ping
+            initialDelaySeconds: 10
+            periodSeconds: 10
+            timeoutSeconds: 2
+            failureThreshold: 3
+          readinessProbe:
+            exec:
+              command:
+                - valkey-cli
+                - ping
+            initialDelaySeconds: 5
+            periodSeconds: 5
+            timeoutSeconds: 2
+            successThreshold: 1
+            failureThreshold: 2