Remove debug prints and unused code

- Remove all debug println statements
- Remove unused service_tracker module
- Remove unused struct fields and methods
- Remove empty placeholder files (cpu.rs, memory.rs, defaults.rs)
- Fix all compiler warnings
- Clean build with zero warnings

Version bump to 0.1.159

agent/src/collectors/disk.rs

@@ -19,10 +19,8 @@ pub struct DiskCollector {
 /// A physical drive with its filesystems
 #[derive(Debug, Clone)]
 struct PhysicalDrive {
-    name: String,                        // e.g., "nvme0n1", "sda" 
+    name: String,                        // e.g., "nvme0n1", "sda"
     health: String,                      // SMART health status
-    temperature_celsius: Option<f32>,    // Drive temperature
-    wear_percent: Option<f32>,           // SSD wear level
     filesystems: Vec<Filesystem>,        // mounted filesystems on this drive
 }
 
@@ -351,8 +349,6 @@ impl DiskCollector {
             let physical_drive = PhysicalDrive {
                 name: drive_name,
                 health: "UNKNOWN".to_string(), // Will be updated with SMART data
-                temperature_celsius: None,
-                wear_percent: None,
                 filesystems,
             };
             physical_drives.push(physical_drive);