Implement pnpm and pnpx support

src/packagemanager/pnpm/dependencyScanner/commandArgumentScanner.js

@@ -0,0 +1,28 @@
+import { resolvePackageVersion } from "../../../api/npmApi.js";
+import { parsePackagesFromArguments } from "../parsing/parsePackagesFromArguments.js";
+
+export function commandArgumentScanner() {
+  return {
+    scan: (args) => scanDependencies(args),
+    shouldScan: () => true, // There's no dry run for pnpm, so we always scan
+  };
+}
+
+async function scanDependencies(args) {
+  const changes = [];
+  const packageUpdates = parsePackagesFromArguments(args);
+
+  for (const packageUpdate of packageUpdates) {
+    var exactVersion = await resolvePackageVersion(
+      packageUpdate.name,
+      packageUpdate.version
+    );
+    if (exactVersion) {
+      packageUpdate.version = exactVersion;
+    }
+
+    changes.push({ ...packageUpdate, type: "add" });
+  }
+
+  return changes;
+}