fix: clear draft store when message is submitted

src/lib/components/InputBar.svelte

@@ -175,6 +175,14 @@
     }
   });
 
+  function clearInput() {
+    inputValue = "";
+    const activeId = get(claudeStore.activeConversationId);
+    if (activeId) {
+      claudeStore.setDraftText(activeId, "");
+    }
+  }
+
   function handleInputChange() {
     // If input is empty, allow history navigation again
     // Otherwise, mark that user has manually typed
@@ -212,7 +220,7 @@
   async function executeSlashCommand(): Promise<boolean> {
     const { command, args } = parseSlashCommand(inputValue);
     if (command) {
-      inputValue = "";
+      clearInput();
       showCommandMenu = false;
       matchingCommands = [];
       await command.execute(args);
@@ -245,7 +253,7 @@
         "error",
         `Unknown command: ${message.split(" ")[0]}. Type /help for available commands.`
       );
-      inputValue = "";
+      clearInput();
       return;
     }
 
@@ -261,7 +269,7 @@
     userHasTyped = false;
 
     isSubmitting = true;
-    inputValue = "";
+    clearInput();
 
     // Capture attachments before clearing
     const currentAttachments = [...attachments];