Implement real-time process monitoring and fix UI hardcoded data

This commit addresses several key issues identified during development:

Major Changes:
- Replace hardcoded top CPU/RAM process display with real system data
- Add intelligent process monitoring to CpuCollector using ps command
- Fix disk metrics permission issues in systemd collector
- Optimize service collection to focus on status, memory, and disk only
- Update dashboard widgets to display live process information

Process Monitoring Implementation:
- Added collect_top_cpu_process() and collect_top_ram_process() methods
- Implemented ps-based monitoring with accurate CPU percentages
- Added filtering to prevent self-monitoring artifacts (ps commands)
- Enhanced error handling and validation for process data
- Dashboard now shows realistic values like "claude (PID 2974) 11.0%"

Service Collection Optimization:
- Removed CPU monitoring from systemd collector for efficiency
- Enhanced service directory permission error logging
- Simplified services widget to show essential metrics only
- Fixed service-to-directory mapping accuracy

UI and Dashboard Improvements:
- Reorganized dashboard layout with btop-inspired multi-panel design
- Updated system panel to include real top CPU/RAM process display
- Enhanced widget formatting and data presentation
- Removed placeholder/hardcoded data throughout the interface

Technical Details:
- Updated agent/src/collectors/cpu.rs with process monitoring
- Modified dashboard/src/ui/mod.rs for real-time process display
- Enhanced systemd collector error handling and disk metrics
- Updated CLAUDE.md documentation with implementation details

shared/src/metrics.rs

@@ -0,0 +1,161 @@
+use serde::{Deserialize, Serialize};
+use chrono::{DateTime, Utc};
+
+/// Individual metric with value, status, and metadata
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Metric {
+    pub name: String,
+    pub value: MetricValue,
+    pub status: Status,
+    pub timestamp: u64,
+    pub description: Option<String>,
+    pub unit: Option<String>,
+}
+
+impl Metric {
+    pub fn new(name: String, value: MetricValue, status: Status) -> Self {
+        Self {
+            name,
+            value,
+            status,
+            timestamp: Utc::now().timestamp() as u64,
+            description: None,
+            unit: None,
+        }
+    }
+    
+    pub fn with_description(mut self, description: String) -> Self {
+        self.description = Some(description);
+        self
+    }
+    
+    pub fn with_unit(mut self, unit: String) -> Self {
+        self.unit = Some(unit);
+        self
+    }
+}
+
+/// Typed metric values
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum MetricValue {
+    Float(f32),
+    Integer(i64),
+    String(String),
+    Boolean(bool),
+}
+
+impl MetricValue {
+    pub fn as_f32(&self) -> Option<f32> {
+        match self {
+            MetricValue::Float(f) => Some(*f),
+            MetricValue::Integer(i) => Some(*i as f32),
+            _ => None,
+        }
+    }
+    
+    pub fn as_i64(&self) -> Option<i64> {
+        match self {
+            MetricValue::Integer(i) => Some(*i),
+            MetricValue::Float(f) => Some(*f as i64),
+            _ => None,
+        }
+    }
+    
+    pub fn as_string(&self) -> String {
+        match self {
+            MetricValue::String(s) => s.clone(),
+            MetricValue::Float(f) => f.to_string(),
+            MetricValue::Integer(i) => i.to_string(),
+            MetricValue::Boolean(b) => b.to_string(),
+        }
+    }
+    
+    pub fn as_bool(&self) -> Option<bool> {
+        match self {
+            MetricValue::Boolean(b) => Some(*b),
+            _ => None,
+        }
+    }
+}
+
+/// Health status for metrics
+#[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, PartialOrd, Ord)]
+pub enum Status {
+    Ok,
+    Warning,
+    Critical,
+    Unknown,
+}
+
+impl Status {
+    /// Aggregate multiple statuses - returns the worst status
+    pub fn aggregate(statuses: &[Status]) -> Status {
+        statuses.iter().max().copied().unwrap_or(Status::Unknown)
+    }
+}
+
+impl Default for Status {
+    fn default() -> Self {
+        Status::Unknown
+    }
+}
+
+/// Metric name registry - constants for all metric names
+pub mod registry {
+    // CPU metrics
+    pub const CPU_LOAD_1MIN: &str = "cpu_load_1min";
+    pub const CPU_LOAD_5MIN: &str = "cpu_load_5min";
+    pub const CPU_LOAD_15MIN: &str = "cpu_load_15min";
+    pub const CPU_TEMPERATURE_CELSIUS: &str = "cpu_temperature_celsius";
+    pub const CPU_FREQUENCY_MHZ: &str = "cpu_frequency_mhz";
+    pub const CPU_USAGE_PERCENT: &str = "cpu_usage_percent";
+    
+    // Memory metrics
+    pub const MEMORY_USAGE_PERCENT: &str = "memory_usage_percent";
+    pub const MEMORY_TOTAL_GB: &str = "memory_total_gb";
+    pub const MEMORY_USED_GB: &str = "memory_used_gb";
+    pub const MEMORY_AVAILABLE_GB: &str = "memory_available_gb";
+    pub const MEMORY_SWAP_TOTAL_GB: &str = "memory_swap_total_gb";
+    pub const MEMORY_SWAP_USED_GB: &str = "memory_swap_used_gb";
+    
+    // Disk metrics (template - actual names include device)
+    pub const DISK_USAGE_PERCENT_TEMPLATE: &str = "disk_{device}_usage_percent";
+    pub const DISK_TEMPERATURE_CELSIUS_TEMPLATE: &str = "disk_{device}_temperature_celsius";
+    pub const DISK_WEAR_PERCENT_TEMPLATE: &str = "disk_{device}_wear_percent";
+    pub const DISK_SPARE_PERCENT_TEMPLATE: &str = "disk_{device}_spare_percent";
+    pub const DISK_HOURS_TEMPLATE: &str = "disk_{device}_hours";
+    pub const DISK_CAPACITY_GB_TEMPLATE: &str = "disk_{device}_capacity_gb";
+    
+    // Service metrics (template - actual names include service)
+    pub const SERVICE_STATUS_TEMPLATE: &str = "service_{name}_status";
+    pub const SERVICE_MEMORY_MB_TEMPLATE: &str = "service_{name}_memory_mb";
+    pub const SERVICE_CPU_PERCENT_TEMPLATE: &str = "service_{name}_cpu_percent";
+    
+    // Backup metrics
+    pub const BACKUP_STATUS: &str = "backup_status";
+    pub const BACKUP_LAST_RUN_TIMESTAMP: &str = "backup_last_run_timestamp";
+    pub const BACKUP_SIZE_GB: &str = "backup_size_gb";
+    pub const BACKUP_DURATION_MINUTES: &str = "backup_duration_minutes";
+    pub const BACKUP_NEXT_SCHEDULED_TIMESTAMP: &str = "backup_next_scheduled_timestamp";
+    
+    // Network metrics (template - actual names include interface)
+    pub const NETWORK_RX_BYTES_TEMPLATE: &str = "network_{interface}_rx_bytes";
+    pub const NETWORK_TX_BYTES_TEMPLATE: &str = "network_{interface}_tx_bytes";
+    pub const NETWORK_RX_PACKETS_TEMPLATE: &str = "network_{interface}_rx_packets";
+    pub const NETWORK_TX_PACKETS_TEMPLATE: &str = "network_{interface}_tx_packets";
+    
+    /// Generate disk metric name from template
+    pub fn disk_metric(template: &str, device: &str) -> String {
+        template.replace("{device}", device)
+    }
+    
+    /// Generate service metric name from template
+    pub fn service_metric(template: &str, name: &str) -> String {
+        template.replace("{name}", name)
+    }
+    
+    /// Generate network metric name from template
+    pub fn network_metric(template: &str, interface: &str) -> String {
+        template.replace("{interface}", interface)
+    }
+}