Add CI check for missing workspace packages in Dockerfiles

Adds a script that verifies every packages/*/package.json is listed in
all app Dockerfiles. Catches the recurring issue where adding a new
workspace package breaks production because the Dockerfile deps stage
doesn't know about it.

Also fixes two pre-existing missing packages in the planner Dockerfile
(api, map-core) caught by the new check.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/check-dockerfiles.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Verify all workspace packages are listed in Dockerfiles.
+# Run in CI to catch missing COPY lines when new packages are added.
+set -euo pipefail
+
+errors=0
+
+for pkg_json in packages/*/package.json; do
+  pkg_dir=$(dirname "$pkg_json")  # e.g. packages/jobs
+  pkg_name=$(basename "$pkg_dir")  # e.g. jobs
+
+  for dockerfile in apps/*/Dockerfile; do
+    app=$(basename "$(dirname "$dockerfile")")
+    if ! grep -q "COPY ${pkg_dir}/package.json" "$dockerfile"; then
+      echo "ERROR: $dockerfile is missing COPY for $pkg_dir/package.json"
+      errors=$((errors + 1))
+    fi
+  done
+done
+
+if [ "$errors" -gt 0 ]; then
+  echo ""
+  echo "$errors missing package(s) in Dockerfiles. Add COPY lines to the deps stage."
+  exit 1
+fi
+
+echo "All workspace packages present in all Dockerfiles."