feat: improve audit log naming with timestamp and app context

Enhances audit log directory naming from `{hostname}_{uuid}` to
`{timestamp}_{appName}_{hostname}_{shortId}` for better discoverability
and benchmarking analysis.

Changes:
- Add extractAppName() helper to extract app name from config files
- Add smart fallback: use port number for localhost without config
- Update generateSessionIdentifier() to include timestamp prefix
- Shorten session ID to first 8 characters for readability

Examples:
- With config: 20251025T193847Z_myapp_localhost_efc60ee0/
- Without config: 20251025T193913Z_8080_localhost_d47e3bfd/
- Remote: 20251024T004401Z_noconfig_example-com_d47e3bfd/

Benefits:
- Chronologically sortable audit logs
- Instant app identification in directory listings
- Efficient filtering for benchmarking queries
- Non-breaking: existing logs keep their names

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

src/audit/utils.js

@@ -17,16 +17,78 @@ export const SHANNON_ROOT = path.resolve(__dirname, '..', '..');
 export const AUDIT_LOGS_DIR = path.join(SHANNON_ROOT, 'audit-logs');
 
 /**
- * Generate standardized session identifier: {hostname}_{sessionId}
+ * Extract application name from config file or URL
+ * @param {string} configFile - Config filename (e.g., "app-config.yaml")
+ * @param {string} webUrl - Target web URL
+ * @returns {string} App name (e.g., "app", "8080", "noconfig")
+ */
+function extractAppName(configFile, webUrl) {
+  // If config file provided, extract app name from it
+  if (configFile) {
+    // Remove .yaml/.yml extension
+    let baseName = configFile.replace(/\.(yaml|yml)$/i, '');
+
+    // Remove path if present (e.g., "configs/app-config.yaml")
+    baseName = baseName.split('/').pop();
+
+    // Extract parts before "config"
+    // app-config → app
+    // my-app-config → myapp
+    const parts = baseName.split('-');
+    const configIndex = parts.indexOf('config');
+
+    if (configIndex > 0) {
+      // Take everything before "config" and join without hyphens
+      return parts.slice(0, configIndex).join('').toLowerCase();
+    }
+
+    // Fallback: just use the whole thing without hyphens
+    return baseName.replace(/-/g, '').toLowerCase();
+  }
+
+  // No config file - use port number for localhost, "noconfig" for remote
+  const url = new URL(webUrl);
+  if (url.hostname === 'localhost' || url.hostname === '127.0.0.1') {
+    // Use port number (default to 80 for http, 443 for https)
+    const port = url.port || (url.protocol === 'https:' ? '443' : '80');
+    return port;
+  }
+
+  // Remote URL without config
+  return 'noconfig';
+}
+
+/**
+ * Generate standardized session identifier with timestamp and app context
+ * Format: {timestamp}_{appName}_{hostname}_{sessionIdShort}
+ * Example: 20251025T193847Z_myapp_localhost_efc60ee0
+ *
  * @param {Object} sessionMetadata - Session metadata from Shannon store
  * @param {string} sessionMetadata.id - UUID session ID
  * @param {string} sessionMetadata.webUrl - Target web URL
+ * @param {string} [sessionMetadata.configFile] - Config filename (optional)
+ * @param {string} [sessionMetadata.createdAt] - ISO 8601 timestamp (optional, defaults to now)
  * @returns {string} Formatted session identifier
  */
 export function generateSessionIdentifier(sessionMetadata) {
-  const { id, webUrl } = sessionMetadata;
+  const { id, webUrl, configFile, createdAt } = sessionMetadata;
+
+  // Extract hostname
   const hostname = new URL(webUrl).hostname.replace(/[^a-zA-Z0-9-]/g, '-');
-  return `${hostname}_${id}`;
+
+  // Extract app name from config file or URL
+  const appName = extractAppName(configFile, webUrl);
+
+  // Format timestamp (use createdAt if available, otherwise use current time)
+  let timestamp = createdAt || new Date().toISOString();
+  // Convert to compact ISO 8601: 2025-10-25T01:37:36.174Z → 20251025T013736Z
+  timestamp = timestamp.replace(/[-:]/g, '').replace(/\.\d{3}Z/, 'Z');
+
+  // Use first 8 characters of session ID for uniqueness
+  const sessionIdShort = id.substring(0, 8);
+
+  // Combine: timestamp_appName_hostname_sessionIdShort
+  return `${timestamp}_${appName}_${hostname}_${sessionIdShort}`;
 }
 
 /**