feat: Disable @radon by default (#1793)

`@radon` is a Chat Participant (CP). CPs don't allow for tool calling,
can't traverse files, etc, etc. - they are very limited in scope
compared to Agents. I assume it's very confusing for new users, that
when you use `@radon`, all other tools stop working (`#view_screenshot`,
`#view_component_tree`, etc.). It looks like something is broken on our
side, while in reality this is simply how it works and there’s no
workaround (VS Code
[docs](https://code.visualstudio.com/docs/copilot/chat/chat-tools#_whats-the-difference-between-tools-and-chat-participants),
and the
[proposal](https://raw.githubusercontent.com/microsoft/vscode/main/src/vscode-dts/vscode.proposed.chatParticipantAdditions.d.ts)
to fix this in VS Code).

`@radon` CP was the very first implementation of Radon AI we've had. It
used to be useful, but today it provides no edge over our agentic set of
tools. All this, while it blocks the use of all all tools, whether that
means reading a file, interacting with git, or checking logs - it's all
blocked when the user decides to include `@radon` in their prompt.
That’s why I think it’s safe to deprecate it. In my opinion, it causes
more harm than good.

By `"I assume it's very confusing for new users"` and `"causes more harm
than good"`, i mean that I've had **multiple** people come up to me,
asking why our AI tools aren't working, only to discover they were
trying to do something like `@radon What's on my screen?`. The tipping
point was this exact thing happening again - today.

**To be discussed further.**

### How Has This Been Tested: 

- Try using `@radon` in the copilot chat - it doesn't work (that's
good).
<img width="185" height="107" alt="image"
src="https://github.com/user-attachments/assets/1102414e-f13d-4242-9736-079f3232a3c5"
/>
- Go to settings, type: `Radon AI: Enable Chat Participant`
<img width="264" height="87" alt="image"
src="https://github.com/user-attachments/assets/399a2f34-6fe3-42d5-9b8f-c05a26bf4b81"
/>
- Check the first option
<img width="376" height="178" alt="image"
src="https://github.com/user-attachments/assets/9a8f55a1-d018-421c-a6bd-d5a88b38e7a7"
/>
- The `@radon` CP is now available in copilot chat.
<img width="197" height="110" alt="image"
src="https://github.com/user-attachments/assets/ac654bbf-700e-4c2a-b059-f870f3e70f2c"
/>


### How Has This Change Been Documented:

Documented in #1794

Author: latekvo

packages/vscode-extension/package.json

@@ -283,7 +283,7 @@
         "title": "Toggle device appearance (light/dark mode)",
         "category": "Radon IDE",
         "enablement": "RNIDE.extensionIsActive && RNIDE.panelIsOpen"
-      }, 
+      },
       {
         "command": "RNIDE.removeLicense",
         "title": "Remove license",
@@ -546,6 +546,13 @@
             "default": true,
             "scope": "window",
             "description": "Enables the Radon AI functionality in the extension."
+          },
+          "RadonIDE.radonAI.enableChatParticipant": {
+            "type": "boolean",
+            "default": false,
+            "scope": "window",
+            "markdownDescription": "**[deprecated]** Enables `@radon` AI chat participant.",
+            "description": "[deprecated] Enables `@radon` AI chat participant."
           }
         }
       }
@@ -1182,6 +1189,7 @@
     },
     "chatParticipants": [
       {
+        "when": "RNIDE.chatParticipantEnabled",
         "id": "chat.radon-ai",
         "fullName": "Radon AI",
         "name": "radon",

packages/vscode-extension/src/ai/mcp/RadonMcpController.ts

@@ -37,6 +37,10 @@ function setGlobalEnableAI(isAIEnabled: boolean) {
   commands.executeCommand("setContext", "RNIDE.AIEnabled", isAIEnabled);
 }
 
+function setGlobalEnableChat(isChatEnabled: boolean) {
+  commands.executeCommand("setContext", "RNIDE.chatParticipantEnabled", isChatEnabled);
+}
+
 /**
   The `vscode.lm.registerTool` API with image support only available in VSCode version 1.105+.  
   Said API is not implemented on Cursor, Windsurf or Antigravity (it is a stub on these editors).
@@ -99,6 +103,12 @@ export function isAiEnabledInSettings() {
   return workspace.getConfiguration("RadonIDE").get<boolean>("radonAI.enabledBoolean") ?? true;
 }
 
+export function isChatEnabledInSettings() {
+  return (
+    workspace.getConfiguration("RadonIDE").get<boolean>("radonAI.enableChatParticipant") ?? false
+  );
+}
+
 async function radonAIAvailabilityStatus() {
   const token = await getLicenseToken();
   if (!token) {
@@ -135,6 +145,10 @@ class RadonMcpController implements Disposable {
   ) {
     this.radonAvailabilityStatus = options.radonAvailabilityStatus;
 
+    setGlobalEnableChat(isChatEnabledInSettings());
+
+    // Registering `@radon` chat regardless of `isChatEnabledInSettings`,
+    // as visibility of the chat participant is toggled within `package.json`.
     registerRadonChat(context, options);
 
     const useStaticRegistering = shouldUseDirectRegistering();
@@ -178,6 +192,9 @@ class RadonMcpController implements Disposable {
     // `setGlobalEnableAI` sets availability of both static and local server tools.
     setGlobalEnableAI(radonAiEnabled);
 
+    // `setGlobalEnableChat` sets availability of `@radon` chat participant
+    setGlobalEnableChat(isChatEnabledInSettings());
+
     if (!shouldUseDirectRegistering()) {
       if (radonAiEnabled) {
         this.enableServer();