fix(ci): extend deploy image readiness poll 10min→90min (DAK-6833) (#202)

ARM Docker builds measured at 30-106 minutes. PR#200 added the retry
loop but with only 10×60s=10min window — far too short to cover even
the average 49-64min ARM build time.

Extend to 90×60s=90min to cover worst-case ARM CI builds.

Co-authored-by: Paperclip <noreply@paperclip.ing>

Author: ferhimedamine

.github/workflows/deploy-production.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Verify Docker image exists
         run: |
           echo "Checking ghcr.io/dakera-ai/dakera:${{ inputs.version }}..."
-          for i in $(seq 1 10); do
+          for i in $(seq 1 90); do
             if docker manifest inspect ghcr.io/dakera-ai/dakera:${{ inputs.version }} > /dev/null 2>&1; then
               echo "✅ Image exists (attempt $i/10)"
               exit 0