feat: Integrate SmartMetrics for enhanced CPU and memory monitoring in UI

readme.hints.md

@@ -903,4 +903,45 @@ The DNS functionality has been refactored from UnifiedEmailServer to a dedicated
 - DNS functionality is now easily discoverable in DnsManager
 - Clear separation between DNS management and email server logic
 - UnifiedEmailServer is simpler and more focused
-- All DNS-related tests pass successfully
+- All DNS-related tests pass successfully
+
+## SmartMetrics Integration (2025-06-12) - COMPLETED
+
+### Overview
+Fixed the UI metrics display to show accurate CPU and memory data from SmartMetrics.
+
+### Key Findings
+1. **CPU Metrics:**
+   - SmartMetrics provides `cpuUsageText` as a string percentage
+   - MetricsManager parses it as `cpuUsage.user` (system is always 0)
+   - UI was incorrectly dividing by 2, showing half the actual CPU usage
+
+2. **Memory Metrics:**
+   - SmartMetrics calculates `maxMemoryMB` as minimum of:
+     - V8 heap size limit
+     - System total memory
+     - Docker memory limit (if available)
+   - Provides `memoryUsageBytes` (total process memory including children)
+   - Provides `memoryPercentage` (pre-calculated percentage)
+   - UI was only showing heap usage, missing actual memory constraints
+
+### Changes Made
+1. **MetricsManager Enhanced:**
+   - Added `maxMemoryMB` from SmartMetrics instance
+   - Added `actualUsageBytes` from SmartMetrics data
+   - Added `actualUsagePercentage` from SmartMetrics data
+   - Kept existing memory fields for compatibility
+
+2. **Interface Updated:**
+   - Added optional fields to `IServerStats.memoryUsage`
+   - Fields are optional to maintain backward compatibility
+
+3. **UI Fixed:**
+   - Removed incorrect CPU division by 2
+   - Uses `actualUsagePercentage` when available (falls back to heap percentage)
+   - Shows actual memory usage vs max memory limit (not just heap)
+
+### Result
+- CPU now shows accurate usage percentage
+- Memory shows percentage of actual constraints (Docker/system/V8 limits)
+- Better monitoring for containerized environments