fix: skip echo relay for Discord-origin user messages

extension/src/extension.ts

@@ -82,6 +82,8 @@ function ensureBridgeDir() {
 // Module-level activeSessionId so writeChatSnapshot can register sessions lazily
 let activeSessionId = '';
 let activeTrajectoryId = '';
+// Track recently sent Discord→AG texts to avoid echo relay
+const recentDiscordSentTexts: Map<string, number> = new Map();
 
 function writeChatSnapshot(text: string) {
     try {
@@ -156,6 +158,7 @@ function processCommandFile(filePath: string) {
             console.log(`Gravity Bridge: auto-approve → ${mode}`);
         } else if (text) {
             // Send message to Antigravity — use VS Code command (most reliable)
+            recentDiscordSentTexts.set(text.trim(), Date.now());
             vscode.commands.executeCommand('antigravity.sendPromptToAgentPanel', text)
                 .then(() => console.log(`Gravity Bridge: ✅ sent "${text.substring(0, 50)}" via sendPromptToAgentPanel`),
                     (e: any) => console.log(`Gravity Bridge: sendPrompt failed: ${e.message}`));
@@ -1863,7 +1866,13 @@ function setupMonitor() {
 
                         logToFile(`[USER-MSG] step=${userInputIdx} type=${umStep?.type} client=${clientType} text=${umText.substring(0, 100)}`);
 
-                        if (umText.length > 2) {
+                        // Skip echo: if this text was recently sent from Discord, don't relay back
+                        const trimmed = umText.trim();
+                        const sentAt = recentDiscordSentTexts.get(trimmed);
+                        if (sentAt && (Date.now() - sentAt) < 60_000) {
+                            recentDiscordSentTexts.delete(trimmed);
+                            logToFile(`[USER-MSG] skipped echo relay (Discord origin, ${Math.round((Date.now()-sentAt)/1000)}s ago)`);
+                        } else if (umText.length > 2) {
                             const truncated = umText.length > 800
                                 ? umText.substring(0, 800) + '\n\n_(이하 생략)_'
                                 : umText;