Refactor container build and installation pipeline to use configurable Makefile parameters (e.g. DISTROS, base images) and propagate them through all build, install, and test scripts

scripts/test/test-container.sh

@@ -0,0 +1,40 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+echo "============================================================"
+echo ">>> Running sanity test: verifying test containers start"
+echo "============================================================"
+
+for distro in $DISTROS; do
+    IMAGE="package-manager-test-$distro"
+
+    echo
+    echo "------------------------------------------------------------"
+    echo ">>> Testing container: $IMAGE"
+    echo "------------------------------------------------------------"
+
+    echo "[test-container] Running: docker run --rm --entrypoint pkgmgr $IMAGE --help"
+    echo
+
+    # Run the command and capture the output
+    if OUTPUT=$(docker run --rm \
+            -e PKGMGR_DEV=1 \
+            -v "$(pwd):/src" \
+            -v "pkgmgr_nix_cache:/root/.cache/nix" \
+            "$IMAGE" 2>&1); then
+        echo "$OUTPUT"
+        echo
+        echo "[test-container] SUCCESS: $IMAGE responded to 'pkgmgr --help'"
+
+    else
+        echo "$OUTPUT"
+        echo
+        echo "[test-container] ERROR: $IMAGE failed to run 'pkgmgr --help'"
+        exit 1
+    fi
+done
+
+echo
+echo "============================================================"
+echo ">>> All containers passed the sanity check"
+echo "============================================================"