feat: extend host load factors

lnvps_db/migrations/20250324143556_load_factors.sql

@@ -0,0 +1,5 @@
+-- Add migration script here
+alter table vm_host
+    add column load_memory float not null default 1.0,
+    add column load_disk float not null default 1.0,
+    change column load_factor load_cpu float not null default 1.0

lnvps_db/src/model.rs

@@ -80,8 +80,12 @@ pub struct VmHost {
     pub enabled: bool,
     /// API token used to control this host via [ip]
     pub api_token: String,
-    /// Load factor for provisioning
-    pub load_factor: f32,
+    /// CPU load factor for provisioning
+    pub load_cpu: f32,
+    /// Memory load factor
+    pub load_memory: f32,
+    /// Disk load factor
+    pub load_disk:f32,
 }
 
 #[derive(FromRow, Clone, Debug, Default)]