feat: add CI/CD script for building Docker images across workspaces

Add ci-build-docker-image.sh script to automate Docker image builds in CI/CD pipelines. Script iterates through configured workspaces and builds images using --auto-version and --auto-push flags. Currently configured for mailgun-webhook, easily extensible for additional workspaces.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

ci-build-docker-image.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+# CI/CD script to build and push Docker images for workspace projects
+# Uses version from package.json and automatically pushes to registry
+
+set -e  # Exit on error
+
+# List of workspaces to build
+WORKSPACES=(
+    "mailgun-webhook"
+)
+
+printf "\n=== CI/CD Docker Image Build ===\n"
+printf "Building %d workspace(s)\n\n" "${#WORKSPACES[@]}"
+
+for WORKSPACE_DIR in "${WORKSPACES[@]}"; do
+    printf "\n--- Building workspace: %s ---\n\n" "$WORKSPACE_DIR"
+
+    if [ ! -d "$WORKSPACE_DIR" ]; then
+        printf "\nERROR: Directory '%s' does not exist. Skipping.\n\n" "$WORKSPACE_DIR"
+        continue
+    fi
+
+    if [ ! -f "$WORKSPACE_DIR/build-image.sh" ]; then
+        printf "\nERROR: build-image.sh not found in '%s'. Skipping.\n\n" "$WORKSPACE_DIR"
+        continue
+    fi
+
+    cd "$WORKSPACE_DIR"
+    ./build-image.sh --auto-version --auto-push
+    cd ..
+
+    printf "\n--- Completed: %s ---\n" "$WORKSPACE_DIR"
+done
+
+printf "\n=== All builds completed successfully! ===\n\n"