feat: add notification sounds (#44)

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Reviewed-on: #44
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/lib/components/InputBar.svelte

@@ -2,6 +2,7 @@
   import { invoke } from "@tauri-apps/api/core";
   import { claudeStore } from "$lib/stores/claude";
   import { characterState } from "$lib/stores/character";
+  import { handleNewUserMessage } from "$lib/notifications/rules";
 
   let inputValue = $state("");
   let isSubmitting = $state(false);
@@ -20,6 +21,9 @@
     isSubmitting = true;
     inputValue = "";
 
+    // Reset notification state for new user message
+    handleNewUserMessage();
+
     claudeStore.addLine("user", message);
     characterState.setState("thinking");