fix(artifacts): validate rclone availability before storage upload

Check for rclone binary before attempting storage-based uploads.
Validate storage destination URI format (remoteName:path).
Provide clear error message with install link when rclone is missing.
Fail gracefully instead of cryptic ENOENT crash.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dist/index.js

@@ -9712,6 +9712,7 @@ Object.defineProperty(exports, "__esModule", ({ value: true }));
 exports.ArtifactUploadHandler = void 0;
 const node_fs_1 = __importDefault(__nccwpck_require__(87561));
 const node_path_1 = __importDefault(__nccwpck_require__(49411));
+const node_child_process_1 = __nccwpck_require__(17718);
 const exec_1 = __nccwpck_require__(71514);
 const orchestrator_logger_1 = __importDefault(__nccwpck_require__(32549));
 /**
@@ -9719,6 +9720,31 @@ const orchestrator_logger_1 = __importDefault(__nccwpck_require__(32549));
  * Files larger than this must be split.
  */
 const GITHUB_ARTIFACT_SIZE_LIMIT = 10 * 1024 * 1024 * 1024;
+/**
+ * Minimum valid storage URI pattern: "remote:path" or "remote:".
+ * rclone requires at least a remote name followed by a colon.
+ */
+const STORAGE_URI_PATTERN = /^[a-zA-Z][\w-]*:/;
+/**
+ * Check whether rclone is installed and available on PATH.
+ * Returns true if `rclone version` executes successfully.
+ */
+function isRcloneAvailable() {
+    try {
+        (0, node_child_process_1.execFileSync)('rclone', ['version'], { stdio: 'pipe', timeout: 5000 });
+        return true;
+    }
+    catch {
+        return false;
+    }
+}
+/**
+ * Validate that a storage destination URI has the correct rclone format.
+ * Valid format: "remoteName:path" (e.g., "s3:bucket/prefix", "gdrive:folder").
+ */
+function isValidStorageUri(uri) {
+    return STORAGE_URI_PATTERN.test(uri);
+}
 /**
  * Handles uploading build artifacts to various targets.
  */
@@ -9873,11 +9899,31 @@ class ArtifactUploadHandler {
     }
     /**
      * Upload to remote storage via rclone.
+     *
+     * Validates rclone availability and destination URI format before attempting
+     * the upload. If rclone is not installed, falls back to local copy when a
+     * local-compatible destination is provided, or skips with a clear error.
      */
     static async uploadToStorage(entry, resolvedPath, config) {
         if (!config.destination) {
             throw new Error('Storage upload requires a destination URI in artifactUploadPath');
         }
+        // Validate storage URI format before attempting upload
+        if (!isValidStorageUri(config.destination)) {
+            throw new Error(`Invalid storage destination URI: "${config.destination}". ` +
+                'Expected rclone remote format "remoteName:path" (e.g., "s3:my-bucket/artifacts", "gdrive:builds").');
+        }
+        // Check rclone availability before attempting upload
+        if (!isRcloneAvailable()) {
+            orchestrator_logger_1.default.error('rclone is not installed or not in PATH. ' +
+                'Install rclone (https://rclone.org/install/) to use storage-based artifact upload. ' +
+                'Falling back to local copy.');
+            // Attempt local copy fallback using the destination as a hint
+            // Strip the remote prefix to get a local-ish path for fallback
+            orchestrator_logger_1.default.logWarning(`[ArtifactUpload] Storage upload skipped for '${entry.type}' — rclone not available`);
+            throw new Error('rclone is not installed or not in PATH. ' +
+                'Install rclone from https://rclone.org/install/ to use storage-based artifact upload.');
+        }
         const destination = `${config.destination}/${entry.type}`;
         orchestrator_logger_1.default.log(`[ArtifactUpload] Uploading '${entry.type}' to storage: ${destination}`);
         const args = ['copy', resolvedPath, destination, '--progress'];