style: apply cargo fmt to entire codebase

Standardize code formatting across all 173 Rust source files
using rustfmt. No functional changes - purely cosmetic.

This establishes a consistent code style baseline for the
project going forward.

src/domain/repositories/settings_repository.rs

@@ -1,27 +1,28 @@
-use std::collections::HashMap;
-use async_trait::async_trait;
-use crate::common::errors::DomainError;
-
-/// Repository for platform settings stored in the database.
-/// Settings are key-value pairs organized by category (e.g., "oidc", "general").
-#[async_trait]
-pub trait SettingsRepository: Send + Sync + 'static {
-    /// Get a single setting value by key
-    async fn get(&self, key: &str) -> Result<Option<String>, DomainError>;
-
-    /// Get all settings for a given category
-    async fn get_by_category(&self, category: &str) -> Result<HashMap<String, String>, DomainError>;
-
-    /// Set a setting value (upsert)
-    async fn set(
-        &self,
-        key: &str,
-        value: &str,
-        category: &str,
-        is_secret: bool,
-        updated_by: Option<&str>,
-    ) -> Result<(), DomainError>;
-
-    /// Delete a setting by key
-    async fn delete(&self, key: &str) -> Result<(), DomainError>;
-}
+use crate::common::errors::DomainError;
+use async_trait::async_trait;
+use std::collections::HashMap;
+
+/// Repository for platform settings stored in the database.
+/// Settings are key-value pairs organized by category (e.g., "oidc", "general").
+#[async_trait]
+pub trait SettingsRepository: Send + Sync + 'static {
+    /// Get a single setting value by key
+    async fn get(&self, key: &str) -> Result<Option<String>, DomainError>;
+
+    /// Get all settings for a given category
+    async fn get_by_category(&self, category: &str)
+    -> Result<HashMap<String, String>, DomainError>;
+
+    /// Set a setting value (upsert)
+    async fn set(
+        &self,
+        key: &str,
+        value: &str,
+        category: &str,
+        is_secret: bool,
+        updated_by: Option<&str>,
+    ) -> Result<(), DomainError>;
+
+    /// Delete a setting by key
+    async fn delete(&self, key: &str) -> Result<(), DomainError>;
+}