Remove hardcoded defaults, require configuration file

- Remove all Default implementations from agent configuration structs
- Make configuration file required for agent startup
- Update NixOS module to generate complete agent.toml configuration
- Add comprehensive configuration options to NixOS module including:
  - Service include/exclude patterns for systemd collector
  - All thresholds and intervals
  - ZMQ communication settings
  - Notification and cache configuration
- Agent now fails fast if no configuration provided
- Eliminates configuration drift between defaults and NixOS settings

agent/src/config/mod.rs

@@ -3,12 +3,9 @@ use cm_dashboard_shared::CacheConfig;
 use serde::{Deserialize, Serialize};
 use std::path::Path;
 
-pub mod defaults;
 pub mod loader;
 pub mod validation;
 
-use defaults::*;
-
 /// Main agent configuration
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AgentConfig {
@@ -58,7 +55,9 @@ pub struct CpuConfig {
 pub struct MemoryConfig {
     pub enabled: bool,
     pub interval_seconds: u64,
+    /// Memory usage warning threshold (percentage)
     pub usage_warning_percent: f32,
+    /// Memory usage critical threshold (percentage)
     pub usage_critical_percent: f32,
 }
 
@@ -67,19 +66,22 @@ pub struct MemoryConfig {
 pub struct DiskConfig {
     pub enabled: bool,
     pub interval_seconds: u64,
+    /// Disk usage warning threshold (percentage)
     pub usage_warning_percent: f32,
+    /// Disk usage critical threshold (percentage)
     pub usage_critical_percent: f32,
+    /// Filesystem configurations
     pub filesystems: Vec<FilesystemConfig>,
 }
 
 /// Filesystem configuration entry
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct FilesystemConfig {
-    pub name: String,           // Human-readable name (e.g., "root", "boot", "home")
-    pub uuid: String,           // UUID for /dev/disk/by-uuid/ resolution
-    pub mount_point: String,    // Expected mount point (e.g., "/", "/boot")
-    pub fs_type: String,        // Filesystem type (e.g., "ext4", "vfat")
-    pub monitor: bool,          // Whether to monitor this filesystem
+    pub name: String,
+    pub uuid: String,
+    pub mount_point: String,
+    pub fs_type: String,
+    pub monitor: bool,
 }
 
 /// Process collector configuration
@@ -95,8 +97,8 @@ pub struct ProcessConfig {
 pub struct SystemdConfig {
     pub enabled: bool,
     pub interval_seconds: u64,
-    pub auto_discover: bool,
-    pub services: Vec<String>,
+    pub service_name_filters: Vec<String>,
+    pub excluded_services: Vec<String>,
     pub memory_warning_mb: f32,
     pub memory_critical_mb: f32,
 }
@@ -126,8 +128,6 @@ pub struct BackupConfig {
 pub struct NetworkConfig {
     pub enabled: bool,
     pub interval_seconds: u64,
-    pub interfaces: Vec<String>,
-    pub auto_discover: bool,
 }
 
 /// Notification configuration
@@ -142,275 +142,11 @@ pub struct NotificationConfig {
 }
 
 impl AgentConfig {
-    pub fn load_from_file<P: AsRef<Path>>(path: P) -> Result<Self> {
+    pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self> {
         loader::load_config(path)
     }
 
     pub fn validate(&self) -> Result<()> {
         validation::validate_config(self)
     }
-}
-
-impl Default for AgentConfig {
-    fn default() -> Self {
-        Self {
-            zmq: ZmqConfig::default(),
-            collectors: CollectorConfig::default(),
-            cache: CacheConfig::default(),
-            notifications: NotificationConfig::default(),
-            collection_interval_seconds: DEFAULT_COLLECTION_INTERVAL_SECONDS,
-        }
-    }
-}
-
-impl Default for ZmqConfig {
-    fn default() -> Self {
-        Self {
-            publisher_port: DEFAULT_ZMQ_PUBLISHER_PORT,
-            command_port: DEFAULT_ZMQ_COMMAND_PORT,
-            bind_address: DEFAULT_ZMQ_BIND_ADDRESS.to_string(),
-            timeout_ms: DEFAULT_ZMQ_TIMEOUT_MS,
-            heartbeat_interval_ms: DEFAULT_ZMQ_HEARTBEAT_INTERVAL_MS,
-        }
-    }
-}
-
-impl Default for CollectorConfig {
-    fn default() -> Self {
-        Self {
-            cpu: CpuConfig::default(),
-            memory: MemoryConfig::default(),
-            disk: DiskConfig::default(),
-            processes: ProcessConfig::default(),
-            systemd: SystemdConfig::default(),
-            smart: SmartConfig::default(),
-            backup: BackupConfig::default(),
-            network: NetworkConfig::default(),
-        }
-    }
-}
-
-impl Default for CpuConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_CPU_INTERVAL_SECONDS,
-            load_warning_threshold: DEFAULT_CPU_LOAD_WARNING,
-            load_critical_threshold: DEFAULT_CPU_LOAD_CRITICAL,
-            temperature_warning_threshold: DEFAULT_CPU_TEMP_WARNING,
-            temperature_critical_threshold: DEFAULT_CPU_TEMP_CRITICAL,
-        }
-    }
-}
-
-impl Default for MemoryConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_MEMORY_INTERVAL_SECONDS,
-            usage_warning_percent: DEFAULT_MEMORY_WARNING_PERCENT,
-            usage_critical_percent: DEFAULT_MEMORY_CRITICAL_PERCENT,
-        }
-    }
-}
-
-impl Default for DiskConfig {
-    fn default() -> Self {
-        let hostname = gethostname::gethostname().to_string_lossy().to_string();
-        let filesystems = get_default_filesystems_for_host(&hostname);
-        
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_DISK_INTERVAL_SECONDS,
-            usage_warning_percent: DEFAULT_DISK_WARNING_PERCENT,
-            usage_critical_percent: DEFAULT_DISK_CRITICAL_PERCENT,
-            filesystems,
-        }
-    }
-}
-
-/// Get default filesystem configurations for known CMTEC hosts
-fn get_default_filesystems_for_host(hostname: &str) -> Vec<FilesystemConfig> {
-    match hostname {
-        "cmbox" => vec![
-            FilesystemConfig {
-                name: "root".to_string(),
-                uuid: "4cade5ce-85a5-4a03-83c8-dfd1d3888d79".to_string(),
-                mount_point: "/".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "boot".to_string(),
-                uuid: "AB4D-62EC".to_string(),
-                mount_point: "/boot".to_string(),
-                fs_type: "vfat".to_string(),
-                monitor: true,
-            },
-        ],
-        "srv02" => vec![
-            FilesystemConfig {
-                name: "root".to_string(),
-                uuid: "5a880608-c79f-458f-a031-30206aa27ca7".to_string(),
-                mount_point: "/".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "boot".to_string(),
-                uuid: "6B2E-2AD9".to_string(),
-                mount_point: "/boot".to_string(),
-                fs_type: "vfat".to_string(),
-                monitor: true,
-            },
-        ],
-        "simonbox" => vec![
-            FilesystemConfig {
-                name: "root".to_string(),
-                uuid: "b74284a9-2899-4f71-bdb0-fd07dc4baab3".to_string(),
-                mount_point: "/".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "boot".to_string(),
-                uuid: "F6A3-AD2B".to_string(),
-                mount_point: "/boot".to_string(),
-                fs_type: "vfat".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "steampool_1".to_string(),
-                uuid: "09300cb7-0938-4dba-8a42-7a7aaf60db51".to_string(),
-                mount_point: "/steampool_1".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "steampool_2".to_string(),
-                uuid: "a2d61a41-3f2a-4760-b62e-5eb8caf50d1a".to_string(),
-                mount_point: "/steampool_2".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-        ],
-        "steambox" => vec![
-            FilesystemConfig {
-                name: "root".to_string(),
-                uuid: "4514ca9f-2d0a-40df-b14b-e342f39c3e6a".to_string(),
-                mount_point: "/".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "boot".to_string(),
-                uuid: "8FD2-1B13".to_string(),
-                mount_point: "/boot".to_string(),
-                fs_type: "vfat".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "steampool".to_string(),
-                uuid: "0ebe8abb-bbe7-4224-947b-86bf38981f60".to_string(),
-                mount_point: "/mnt/steampool".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-        ],
-        "srv01" => vec![
-            FilesystemConfig {
-                name: "root".to_string(),
-                uuid: "cd98df34-03a3-4d68-8338-d90d2920f9f8".to_string(),
-                mount_point: "/".to_string(),
-                fs_type: "ext4".to_string(),
-                monitor: true,
-            },
-            FilesystemConfig {
-                name: "boot".to_string(),
-                uuid: "13E1-4DDE".to_string(),
-                mount_point: "/boot".to_string(),
-                fs_type: "vfat".to_string(),
-                monitor: true,
-            },
-        ],
-        // labbox and wslbox have no UUIDs configured yet
-        "labbox" | "wslbox" => {
-            Vec::new()
-        },
-        _ => {
-            // Unknown hosts use auto-discovery
-            Vec::new()
-        }
-    }
-}
-
-impl Default for ProcessConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_PROCESS_INTERVAL_SECONDS,
-            top_processes_count: DEFAULT_TOP_PROCESSES_COUNT,
-        }
-    }
-}
-
-impl Default for SystemdConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_SYSTEMD_INTERVAL_SECONDS,
-            auto_discover: true,
-            services: Vec::new(),
-            memory_warning_mb: DEFAULT_SERVICE_MEMORY_WARNING_MB,
-            memory_critical_mb: DEFAULT_SERVICE_MEMORY_CRITICAL_MB,
-        }
-    }
-}
-
-impl Default for SmartConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_SMART_INTERVAL_SECONDS,
-            temperature_warning_celsius: DEFAULT_SMART_TEMP_WARNING,
-            temperature_critical_celsius: DEFAULT_SMART_TEMP_CRITICAL,
-            wear_warning_percent: DEFAULT_SMART_WEAR_WARNING,
-            wear_critical_percent: DEFAULT_SMART_WEAR_CRITICAL,
-        }
-    }
-}
-
-impl Default for BackupConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_BACKUP_INTERVAL_SECONDS,
-            backup_paths: Vec::new(),
-            max_age_hours: DEFAULT_BACKUP_MAX_AGE_HOURS,
-        }
-    }
-}
-
-impl Default for NetworkConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            interval_seconds: DEFAULT_NETWORK_INTERVAL_SECONDS,
-            interfaces: Vec::new(),
-            auto_discover: true,
-        }
-    }
-}
-
-impl Default for NotificationConfig {
-    fn default() -> Self {
-        Self {
-            enabled: true,
-            smtp_host: DEFAULT_SMTP_HOST.to_string(),
-            smtp_port: DEFAULT_SMTP_PORT,
-            from_email: DEFAULT_FROM_EMAIL.to_string(),
-            to_email: DEFAULT_TO_EMAIL.to_string(),
-            rate_limit_minutes: DEFAULT_NOTIFICATION_RATE_LIMIT_MINUTES,
-        }
-    }
-}
+}