runner: introduce CoreExecutor box for JSON→exec; wire Gate‑C pipe to CoreExecutor. Stage‑B bundling: duplicate name Fail‑Fast + mix canary; add Core Map/String positive smokes; add Gate‑C budget opt‑in canary; docs: Exit Code Policy; apply child_env in PyVM common util.

tools/plugins/build-all.sh

@@ -0,0 +1,77 @@
+#!/bin/bash
+# build-all.sh — Build and stage dynamic plugin .so/.dylib/.dll into plugins/*
+# Usage: tools/plugins/build-all.sh [crate_dir ...]
+
+set -euo pipefail
+
+ROOT="${NYASH_ROOT:-$(git rev-parse --show-toplevel 2>/dev/null || pwd)}"
+cd "$ROOT"
+
+detect_ext() {
+  case "$(uname -s)" in
+    Darwin) echo dylib ;;
+    MINGW*|MSYS*|CYGWIN*|Windows_NT) echo dll ;;
+    *) echo so ;;
+  esac
+}
+
+lib_name_for() {
+  local base="$1"; local ext="$2"
+  if [ "$ext" = dll ]; then echo "${base}.dll"; else echo "lib${base}.${ext}"; fi
+}
+
+build_and_stage() {
+  local crate_dir="$1"     # e.g., nyash-counter-plugin
+  local base_name="$2"     # e.g., nyash_counter_plugin
+  local ext
+  ext=$(detect_ext)
+  echo "[plugins/build-all] building: $crate_dir" >&2
+  cargo build --release -p "$crate_dir" >/dev/null
+  local src
+  case "$ext" in
+    dll)   src="target/release/${base_name}.dll" ;;
+    dylib) src="target/release/lib${base_name}.dylib" ;;
+    so)    src="target/release/lib${base_name}.so" ;;
+  esac
+  if [ ! -f "$src" ]; then
+    echo "[plugins/build-all] WARN: built artifact not found: $src" >&2
+    return 1
+  fi
+  local out_dir="plugins/${crate_dir}"
+  mkdir -p "$out_dir"
+  local dst="$out_dir/$(lib_name_for "$base_name" "$ext")"
+  cp -f "$src" "$dst"
+  echo "[plugins/build-all] staged: $dst" >&2
+}
+
+CRATES=(
+  nyash-fixture-plugin:nyash_fixture_plugin
+  nyash-counter-plugin:nyash_counter_plugin
+  nyash-math-plugin:nyash_math_plugin
+  nyash-string-plugin:nyash_string_plugin
+  nyash-console-plugin:nyash_console_plugin
+)
+
+if [ "$#" -gt 0 ]; then
+  # Accept explicit crate_dir list
+  for dir in "$@"; do
+    case "$dir" in
+      nyash-*-plugin)
+        base="${dir//-/_}" # hyphen→underscore
+        build_and_stage "$dir" "$base" || true
+        ;;
+      *)
+        echo "[plugins/build-all] WARN: unknown crate dir pattern: $dir" >&2
+        ;;
+    esac
+  done
+else
+  for ent in "${CRATES[@]}"; do
+    IFS=: read -r dir base <<<"$ent"
+    if [ -d "plugins/$dir" ]; then
+      build_and_stage "$dir" "$base" || true
+    fi
+  done
+fi
+
+echo "[plugins/build-all] done" >&2