Only add /research prefix when no slash command in message on web app

- Explictly adding a slash command is a higher priority intent than
  research mode being enabled in the background. Respect that for a
  more intuitive UX flow.

- Explicit slash commands do not currently work in research mode.
  You've to turn research mode off to use other slash commands. This
  is strange, unnecessary given intent priority is clear.

src/interface/web/app/components/chatInputArea/chatInputArea.tsx

@@ -170,7 +170,12 @@ export const ChatInputArea = forwardRef<HTMLTextAreaElement, ChatInputProps>((pr
         }
 
         let messageToSend = message.trim();
-        if (useResearchMode && !messageToSend.startsWith("/research")) {
+        // Check if message starts with an explicit slash command
+        const startsWithSlashCommand =
+            props.chatOptionsData &&
+            Object.keys(props.chatOptionsData).some((cmd) => messageToSend.startsWith(`/${cmd}`));
+        // Only add /research if useResearchMode is enabled and message doesn't already use a slash command
+        if (useResearchMode && !startsWithSlashCommand) {
             messageToSend = `/research ${messageToSend}`;
         }