Bug fix bf-3dy1: Add R2 credentials to worker deployment for direct replay upload

The worker was only configured with B2 (ARMOR) credentials, so replays were
being uploaded to B2 but not to R2. The index builder's B2→R2 promotion
cycle only covers the last 24 hours, so older replays were not available
in R2, causing 404 errors when clicking "Watch Replay".

This fix adds R2 credentials to the worker deployment, allowing it to
upload replays directly to R2 (hot cache) in addition to B2 (cold archive).
This makes replays immediately available for viewing without waiting for
the promotion cycle.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

manifests/acb-worker-deployment.yml

@@ -78,6 +78,26 @@ spec:
                   key: auth-secret-key
             - name: ACB_B2_REGION
               value: ""
+            - name: ACB_R2_ENDPOINT
+              valueFrom:
+                secretKeyRef:
+                  name: acb-r2-credentials
+                  key: endpoint
+            - name: ACB_R2_BUCKET
+              valueFrom:
+                secretKeyRef:
+                  name: acb-r2-credentials
+                  key: bucket
+            - name: ACB_R2_ACCESS_KEY
+              valueFrom:
+                secretKeyRef:
+                  name: acb-r2-credentials
+                  key: access-key
+            - name: ACB_R2_SECRET_KEY
+              valueFrom:
+                secretKeyRef:
+                  name: acb-r2-credentials
+                  key: secret-key
             - name: ACB_METRICS_ADDR
               value: ":9090"
           resources: