fix: bot text confirmation on relay + rename @bridge to @gravity + channel dedup

extension/package.json

@@ -27,8 +27,8 @@
     "contributes": {
         "chatParticipants": [
             {
-                "id": "gravity-bridge.bridge",
-                "name": "bridge",
+                "id": "gravity-bridge.gravity",
+                "name": "gravity",
                 "fullName": "Gravity Bridge",
                 "description": "대화 히스토리를 Discord로 전송 + AI 제어",
                 "isSticky": false
@@ -72,4 +72,4 @@
             }
         }
     }
-}
+}

extension/src/extension.ts

@@ -107,7 +107,7 @@ export function activate(context: vscode.ExtensionContext) {
     // Register @bridge Chat Participant for history relay
     try {
         const participant = vscode.chat.createChatParticipant(
-            'gravity-bridge.bridge',
+            'gravity-bridge.gravity',
             bridgeChatHandler
         );
         participant.iconPath = new vscode.ThemeIcon('radio-tower');