Complete atomic migration to structured data architecture

Implements clean structured data collection eliminating all string metric
parsing bugs. Collectors now populate AgentData directly with type-safe
field access.

Key improvements:
- Mount points preserved correctly (/ and /boot instead of root/boot)
- Tmpfs discovery added to memory collector
- Temperature data flows as typed f32 fields
- Zero string parsing overhead
- Complete removal of MetricCollectionManager bridge
- Direct ZMQ transmission of structured JSON

All functionality maintained: service tracking, notifications, status
evaluation, and multi-host monitoring.

agent/src/config/mod.rs

@@ -6,8 +6,6 @@ use std::path::Path;
 pub mod loader;
 pub mod validation;
 
-use crate::status::HostStatusConfig;
-
 /// Main agent configuration
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AgentConfig {
@@ -15,7 +13,6 @@ pub struct AgentConfig {
     pub collectors: CollectorConfig,
     pub cache: CacheConfig,
     pub notifications: NotificationConfig,
-    pub status_aggregation: HostStatusConfig,
     pub collection_interval_seconds: u64,
 }