feat: add discord rich presence (#105)

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- [ ] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
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### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
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Reviewed-on: #105
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/lib/stores/config.test.ts

@@ -192,6 +192,7 @@ describe("config store", () => {
         session_cost_budget: null,
         budget_action: "warn",
         budget_warning_threshold: 0.8,
+        discord_rpc_enabled: true,
       };
 
       expect(config.model).toBe("claude-sonnet-4");
@@ -237,6 +238,7 @@ describe("config store", () => {
         session_cost_budget: null,
         budget_action: "warn",
         budget_warning_threshold: 0.8,
+        discord_rpc_enabled: true,
       };
 
       expect(config.model).toBeNull();

src/lib/stores/config.ts

@@ -44,6 +44,8 @@ export interface HikariConfig {
   session_cost_budget: number | null;
   budget_action: BudgetAction;
   budget_warning_threshold: number;
+  // Discord RPC settings
+  discord_rpc_enabled: boolean;
 }
 
 const defaultConfig: HikariConfig = {
@@ -83,6 +85,7 @@ const defaultConfig: HikariConfig = {
   session_cost_budget: null,
   budget_action: "warn",
   budget_warning_threshold: 0.8,
+  discord_rpc_enabled: true,
 };
 
 function createConfigStore() {

src/lib/stores/conversations.ts

@@ -35,6 +35,7 @@ export interface Conversation {
   lastActivityAt: Date;
   attachments: Attachment[];
   summary: ConversationSummary | null;
+  startedAt: Date;
 }
 
 function createConversationsStore() {
@@ -72,6 +73,7 @@ function createConversationsStore() {
       lastActivityAt: new Date(),
       attachments: [],
       summary: null,
+      startedAt: new Date(),
     };
   }
 

src/lib/stores/stats.ts

@@ -2,6 +2,7 @@ import { writable, derived } from "svelte/store";
 import { listen } from "@tauri-apps/api/event";
 import { invoke } from "@tauri-apps/api/core";
 import { costTrackingStore } from "./costTracking";
+import { configStore } from "./config";
 
 export type ContextWarning = "moderate" | "high" | "critical";
 export type BudgetType = "token" | "cost";
@@ -133,7 +134,7 @@ export function formatTokenCount(tokens: number): string {
 }
 
 // Derived store for formatted display values
-export const formattedStats = derived(stats, ($stats) => {
+export const formattedStats = derived([stats, configStore.config], ([$stats, $config]) => {
   const formatNumber = (num: number) => num.toLocaleString();
   const formatCost = (cost: number) => `$${cost.toFixed(4)}`;
   const formatDuration = (seconds: number) => {
@@ -164,6 +165,9 @@ export const formattedStats = derived(stats, ($stats) => {
     }));
   };
 
+  // Use the model from stats if available, otherwise fall back to the configured model
+  const currentModel = $stats.model ?? $config.model ?? "No model selected";
+
   return {
     totalTokens: formatNumber($stats.total_input_tokens + $stats.total_output_tokens),
     totalInputTokens: formatNumber($stats.total_input_tokens),
@@ -173,7 +177,7 @@ export const formattedStats = derived(stats, ($stats) => {
     sessionInputTokens: formatNumber($stats.session_input_tokens),
     sessionOutputTokens: formatNumber($stats.session_output_tokens),
     sessionCost: formatCost($stats.session_cost_usd),
-    model: $stats.model || "No model selected",
+    model: currentModel,
 
     // New formatted fields
     messagesTotal: formatNumber($stats.messages_exchanged),