feat: add discord rich presence (#105)

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Reviewed-on: #105
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src-tauri/src/config.rs

@@ -112,6 +112,9 @@ pub struct HikariConfig {
 
     #[serde(default = "default_budget_warning_threshold")]
     pub budget_warning_threshold: f32,
+
+    #[serde(default = "default_discord_rpc_enabled")]
+    pub discord_rpc_enabled: bool,
 }
 
 impl Default for HikariConfig {
@@ -144,6 +147,7 @@ impl Default for HikariConfig {
             session_cost_budget: None,
             budget_action: BudgetAction::Warn,
             budget_warning_threshold: 0.8,
+            discord_rpc_enabled: true,
         }
     }
 }
@@ -176,6 +180,10 @@ fn default_budget_warning_threshold() -> f32 {
     0.8
 }
 
+fn default_discord_rpc_enabled() -> bool {
+    true
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, Default, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum BudgetAction {
@@ -247,6 +255,7 @@ mod tests {
         assert!(config.session_cost_budget.is_none());
         assert_eq!(config.budget_action, BudgetAction::Warn);
         assert!((config.budget_warning_threshold - 0.8).abs() < f32::EPSILON);
+        assert!(config.discord_rpc_enabled);
     }
 
     #[test]
@@ -279,6 +288,7 @@ mod tests {
             session_cost_budget: Some(1.50),
             budget_action: BudgetAction::Block,
             budget_warning_threshold: 0.75,
+            discord_rpc_enabled: true,
         };
 
         let json = serde_json::to_string(&config).unwrap();