ops: mount HRRR data NFS share at /data

Adds the same NFS volume that microwaveprop uses (10.0.15.103:/data) so
towerops can read the shared HRRR grids and render maps from them.

k8s/deployment.yaml

@@ -232,3 +232,11 @@ spec:
             timeoutSeconds: 2
             successThreshold: 3 # Require 3 consecutive successes (15s) before marking ready
             failureThreshold: 2 # Allow 1 failure before marking not ready
+          volumeMounts:
+            - name: data
+              mountPath: /data
+      volumes:
+        - name: data
+          nfs:
+            server: 10.0.15.103
+            path: /data