build: pin demo toolchains

tools/check-upgrades-cli.mjs

@@ -0,0 +1,28 @@
+import { readFile } from "node:fs/promises";
+import { createRequire } from "node:module";
+
+const require = createRequire(import.meta.url);
+const expectedVersion = "1.46.0";
+const pluginSource = await readFile(
+  new URL("../lib/openzeppelin-foundry-upgrades/src/internal/Versions.sol", import.meta.url),
+  "utf8"
+);
+const lockfile = JSON.parse(
+  await readFile(new URL("../package-lock.json", import.meta.url), "utf8")
+);
+const lockedVersion = lockfile.packages?.["node_modules/@openzeppelin/upgrades-core"]?.version;
+const installedVersion = require("@openzeppelin/upgrades-core/package.json").version;
+
+if (!pluginSource.includes('UPGRADES_CORE = "^1.45.0"')) {
+  throw new Error('Expected the vendored plugin to declare UPGRADES_CORE = "^1.45.0".');
+}
+
+if (lockedVersion !== expectedVersion) {
+  throw new Error(`Expected package-lock.json to resolve @openzeppelin/upgrades-core to ${expectedVersion}, found ${lockedVersion}.`);
+}
+
+if (installedVersion !== expectedVersion) {
+  throw new Error(`Expected installed @openzeppelin/upgrades-core to report ${expectedVersion}, found ${installedVersion}.`);
+}
+
+console.log(`@openzeppelin/upgrades-core ${expectedVersion} is pinned and installed.`);