fix(cli): address PR review feedback for non-interactive install defaults

- Validate cwd with validateDirectorySync in --yes path
- Fix JSDoc placement: move collectCoreConfig docs above its method
- Read user_name default from module.yaml, fall back to OS username
- Harden YAML defaults with type/empty-string normalization
- Log warning on module.yaml load failure instead of silent catch
- Fix backfill predicate to detect unresolved placeholders like {output_folder}
- Always merge defaults into existing config in --yes mode

tools/cli/lib/ui.js

@@ -49,7 +49,12 @@ class UI {
       await prompts.log.info(`Using directory from command-line: ${confirmedDirectory}`);
     } else if (options.yes) {
       // Default to current directory when --yes flag is set
-      confirmedDirectory = process.cwd();
+      const cwd = process.cwd();
+      const validation = this.validateDirectorySync(cwd);
+      if (validation) {
+        throw new Error(`Invalid current directory: ${validation}`);
+      }
+      confirmedDirectory = cwd;
       await prompts.log.info(`Using current directory (--yes flag): ${confirmedDirectory}`);
     } else {
       confirmedDirectory = await this.getConfirmedDirectory();
@@ -846,12 +851,6 @@ class UI {
     return { existingInstall, installedModuleIds, bmadDir };
   }
 
-  /**
-   * Collect core configuration
-   * @param {string} directory - Installation directory
-   * @param {Object} options - Command-line options
-   * @returns {Object} Core configuration
-   */
   /**
    * Get default core config values by reading from src/core/module.yaml
    * @returns {Object} Default core config with user_name, communication_language, document_output_language, output_folder
@@ -866,22 +865,24 @@ class UI {
     } catch {
       safeUsername = process.env.USER || process.env.USERNAME || 'User';
     }
-    const defaultUsername = safeUsername.charAt(0).toUpperCase() + safeUsername.slice(1);
+    const osUsername = safeUsername.charAt(0).toUpperCase() + safeUsername.slice(1);
+
+    const norm = (value, fallback) => (typeof value === 'string' && value.trim() !== '' ? value.trim() : fallback);
 
     // Read defaults from core module.yaml (single source of truth)
     try {
       const moduleYamlPath = path.join(getModulePath('core'), 'module.yaml');
       const moduleConfig = yaml.parse(fs.readFileSync(moduleYamlPath, 'utf8'));
       return {
-        user_name: defaultUsername,
+        user_name: norm(moduleConfig.user_name?.default, osUsername),
-        communication_language: moduleConfig.communication_language?.default || 'English',
+        communication_language: norm(moduleConfig.communication_language?.default, 'English'),
-        document_output_language: moduleConfig.document_output_language?.default || 'English',
+        document_output_language: norm(moduleConfig.document_output_language?.default, 'English'),
-        output_folder: moduleConfig.output_folder?.default || '_bmad-output',
+        output_folder: norm(moduleConfig.output_folder?.default, '_bmad-output'),
       };
-    } catch {
+    } catch (error) {
-      // Fallback if module.yaml is unreadable
+      console.warn(`Failed to load module.yaml, falling back to defaults: ${error.message}`);
       return {
-        user_name: defaultUsername,
+        user_name: osUsername,
         communication_language: 'English',
         document_output_language: 'English',
         output_folder: '_bmad-output',
@@ -889,6 +890,12 @@ class UI {
     }
   }
 
+  /**
+   * Collect core configuration
+   * @param {string} directory - Installation directory
+   * @param {Object} options - Command-line options
+   * @returns {Object} Core configuration
+   */
   async collectCoreConfig(directory, options = {}) {
     const { ConfigCollector } = require('../installers/lib/core/config-collector');
     const configCollector = new ConfigCollector();
@@ -928,21 +935,31 @@ class UI {
         await configCollector.collectModuleConfig('core', directory, false, true);
       } else if (options.yes) {
         // Fill in defaults for any fields not provided via command-line or existing config
+        const isMissingOrUnresolved = (v) => v == null || (typeof v === 'string' && (v.trim() === '' || /^\{[^}]+\}$/.test(v.trim())));
+
         const defaults = this.getDefaultCoreConfig();
         for (const [key, value] of Object.entries(defaults)) {
-          if (!configCollector.collectedConfig.core[key]) {
+          if (isMissingOrUnresolved(configCollector.collectedConfig.core[key])) {
             configCollector.collectedConfig.core[key] = value;
           }
         }
       }
     } else if (options.yes) {
-      // Use all defaults when --yes flag is set
+      // Use all defaults when --yes flag is set, merging with any existing config
       await configCollector.loadExistingConfig(directory);
       const existingConfig = configCollector.collectedConfig.core || {};
+      const defaults = this.getDefaultCoreConfig();
+      configCollector.collectedConfig.core = { ...defaults, ...existingConfig };
+
+      // Clean up any unresolved placeholder tokens from existing config
+      const isMissingOrUnresolved = (v) => v == null || (typeof v === 'string' && (v.trim() === '' || /^\{[^}]+\}$/.test(v.trim())));
+      for (const [key, value] of Object.entries(configCollector.collectedConfig.core)) {
+        if (isMissingOrUnresolved(value)) {
+          configCollector.collectedConfig.core[key] = defaults[key];
+        }
+      }
 
-      // If no existing config, use defaults
       if (Object.keys(existingConfig).length === 0) {
-        configCollector.collectedConfig.core = this.getDefaultCoreConfig();
         await prompts.log.info('Using default configuration (--yes flag)');
       }
     } else {