fix(deploy): reclaim stale build storage

allstarr.Tests/ComposeContractTests.cs

@@ -150,6 +150,7 @@ public sealed class ComposeContractTests
         Assert.Contains("--profile apple", controller, StringComparison.Ordinal);
         Assert.Contains("git diff --quiet && git diff --cached --quiet", controller, StringComparison.Ordinal);
         Assert.Contains("git pull --ff-only", controller, StringComparison.Ordinal);
+        Assert.Contains("docker builder prune --force --min-free-space 8GB", controller, StringComparison.Ordinal);
         Assert.Contains("tracked source files have local changes", controller, StringComparison.Ordinal);
         Assert.Contains("prepare-apple) prepare_apple \"$@\" ;;", controller, StringComparison.Ordinal);
         Assert.Contains("up -d --remove-orphans --wait --wait-timeout 180", controller, StringComparison.Ordinal);

allstarr.sh

@@ -203,6 +203,8 @@ update() {
     git diff --quiet && git diff --cached --quiet ||
       die "tracked source files have local changes; commit or stash them before updating"
     git pull --ff-only
+    docker image prune --force
+    docker builder prune --force --min-free-space 8GB
     docker compose "${COMPOSE[@]}" build allstarr
     if profiles | grep -qx apple; then
       docker compose "${COMPOSE[@]}" build apple-gateway