refactor: change function definitions to const for improved performance and clarity

src-tauri/src/config/prfitem.rs

@@ -611,6 +611,6 @@ impl PrfItem {
 }
 
 // 向前兼容，默认为订阅启用自动更新
-fn default_allow_auto_update() -> Option<bool> {
+const fn default_allow_auto_update() -> Option<bool> {
     Some(true)
 }

src-tauri/src/config/profiles.rs

@@ -102,12 +102,12 @@ impl IProfiles {
         }
     }
 
-    pub fn get_current(&self) -> Option<&String> {
+    pub const fn get_current(&self) -> Option<&String> {
         self.current.as_ref()
     }
 
     /// get items ref
-    pub fn get_items(&self) -> Option<&Vec<PrfItem>> {
+    pub const fn get_items(&self) -> Option<&Vec<PrfItem>> {
         self.items.as_ref()
     }
 

src-tauri/src/config/verge.rs

@@ -531,7 +531,7 @@ impl IVerge {
         patch!(enable_external_controller);
     }
 
-    pub fn get_singleton_port() -> u16 {
+    pub const fn get_singleton_port() -> u16 {
         crate::constants::network::ports::SINGLETON_SERVER
     }