feat(FN-3470): prefer source aliases for runtime plugins and add test artif

Merges FN-3470 in two steps: first, runtime plugins now prefer source path aliases over build artifacts, with hardening tests for vitest alias resolution and plugin view registry updates; second, a new `ensure-test-artifacts.mjs` bootstrap script guarantees required test files exist before test runs

Fusion-Task-Id: FN-3470

scripts/ensure-test-artifacts.mjs

@@ -0,0 +1,38 @@
+#!/usr/bin/env node
+
+import { existsSync } from "node:fs";
+import path from "node:path";
+import { spawnSync } from "node:child_process";
+
+export const REQUIRED_BUILD_PACKAGES = [
+  { name: "@fusion/core", distEntry: "packages/core/dist/index.js" },
+  { name: "@fusion/plugin-sdk", distEntry: "packages/plugin-sdk/dist/index.js" },
+  { name: "@fusion-plugin-examples/hermes-runtime", distEntry: "plugins/fusion-plugin-hermes-runtime/dist/index.js" },
+  { name: "@fusion-plugin-examples/openclaw-runtime", distEntry: "plugins/fusion-plugin-openclaw-runtime/dist/index.js" },
+  { name: "@fusion-plugin-examples/paperclip-runtime", distEntry: "plugins/fusion-plugin-paperclip-runtime/dist/index.js" },
+];
+
+export function detectMissingArtifacts(rootDir = process.cwd(), existsFn = existsSync) {
+  return REQUIRED_BUILD_PACKAGES.filter((pkg) => !existsFn(path.join(rootDir, pkg.distEntry)));
+}
+
+function run(command, args, cwd) {
+  const result = spawnSync(command, args, { cwd, stdio: "inherit" });
+  if (result.status !== 0) {
+    process.exit(result.status ?? 1);
+  }
+}
+
+export function ensureTestArtifacts(rootDir = process.cwd(), runFn = run, existsFn = existsSync) {
+  const missing = detectMissingArtifacts(rootDir, existsFn);
+  if (missing.length === 0) return [];
+
+  const names = missing.map((pkg) => pkg.name);
+  console.log(`[test-bootstrap] building missing dist artifacts: ${names.join(", ")}`);
+  runFn("pnpm", [...names.flatMap((name) => ["--filter", name]), "build"], rootDir);
+  return names;
+}
+
+if (import.meta.url === `file://${process.argv[1]}`) {
+  ensureTestArtifacts();
+}