fix(bridge): 채널 중복 생성 race condition 수정 + AG- 접두사 + metadata 모니터링

bot.py

@@ -33,26 +33,37 @@ def detect_project_name(conv_dir: Path) -> str:
     """Extract a human-readable project name from conversation artifacts.
 
     Strategy:
-    1. Check task.md first line for a title (# Title)
-    2. Check implementation_plan.md first line
+    1. Check task.md first heading for a title
+    2. Check implementation_plan.md first heading
     3. Check any .metadata.json for summary keywords
     4. Fallback to short conversation ID
+
+    Output format: lowercase_with_underscores (e.g. 'gravity_control')
     """
     short_id = conv_dir.name[:8]
 
+    def _sanitize(raw: str) -> str:
+        """Convert raw title to Discord-friendly channel name part."""
+        # Remove common suffixes
+        for suffix in ["Task Tracker", "— Task Tracker", "태스크", "구현 계획"]:
+            raw = raw.replace(suffix, "")
+        raw = raw.strip(" —-–")
+        # Keep only alphanumeric, Korean, spaces, hyphens
+        raw = re.sub(r'[^a-zA-Z0-9가-힣\s\-]', '', raw)
+        # Convert to underscore format
+        raw = re.sub(r'[\s\-]+', '_', raw).strip('_').lower()
+        return raw[:30] if raw else ""
+
     # Try task.md title
     task_file = conv_dir / "task.md"
     if task_file.exists():
         try:
             first_lines = task_file.read_text(encoding="utf-8").splitlines()[:5]
             for line in first_lines:
-                match = re.match(r'^#\s+(.+?)[\s—\-]+', line)
+                match = re.match(r'^#\s+(.+)', line)
                 if match:
-                    name = match.group(1).strip()
-                    # Sanitize for Discord channel name
-                    name = re.sub(r'[^a-zA-Z0-9가-힣\s\-]', '', name)
-                    name = re.sub(r'\s+', '-', name).lower()[:30]
-                    if name:
+                    name = _sanitize(match.group(1))
+                    if name and name != "task":
                         return name
         except (OSError, UnicodeDecodeError):
             pass
@@ -63,26 +74,23 @@ def detect_project_name(conv_dir: Path) -> str:
         try:
             first_lines = plan_file.read_text(encoding="utf-8").splitlines()[:5]
             for line in first_lines:
-                match = re.match(r'^#\s+(.+?)[\s—\-]+', line)
+                match = re.match(r'^#\s+(.+)', line)
                 if match:
-                    name = match.group(1).strip()
-                    name = re.sub(r'[^a-zA-Z0-9가-힣\s\-]', '', name)
-                    name = re.sub(r'\s+', '-', name).lower()[:30]
+                    name = _sanitize(match.group(1))
                     if name:
                         return name
         except (OSError, UnicodeDecodeError):
             pass
 
-    # Try metadata summary
+    # Try metadata summary (first 2 words)
     for meta_file in conv_dir.glob("*.metadata.json"):
         try:
             meta = json.loads(meta_file.read_text(encoding="utf-8"))
             summary = meta.get("summary", "")
-            # Extract first meaningful noun/phrase
-            words = summary.split()[:3]
+            words = summary.split()[:2]
             if words:
-                name = "-".join(words).lower()
-                name = re.sub(r'[^a-z0-9가-힣\-]', '', name)[:30]
+                name = "_".join(words).lower()
+                name = re.sub(r'[^a-z0-9가-힣_]', '', name)[:30]
                 if name:
                     return name
         except (OSError, json.JSONDecodeError):
@@ -123,6 +131,8 @@ class GravityBot(commands.Bot):
         self.session_status_messages: dict[str, int] = {}
         # conversation_id -> project name
         self.session_names: dict[str, str] = {}
+        # Locks to prevent duplicate channel creation
+        self._channel_locks: dict[str, asyncio.Lock] = {}
         # Category for session channels
         self.session_category: discord.CategoryChannel | None = None
         # Guild reference
@@ -184,49 +194,58 @@ class GravityBot(commands.Bot):
     async def _ensure_channel(
         self, conversation_id: str, project_name: str
     ) -> discord.TextChannel:
-        """Get or create a Discord channel for a session."""
-        # Check if channel already exists
+        """Get or create a Discord channel for a session (thread-safe)."""
+        # Fast path: already mapped
         if conversation_id in self.session_channels:
             return self.session_channels[conversation_id]
 
-        channel_name = f"{Config.CHANNEL_PREFIX}-{project_name}"
+        # Get or create a lock for this conversation
+        if conversation_id not in self._channel_locks:
+            self._channel_locks[conversation_id] = asyncio.Lock()
 
-        # Check if channel already exists in category (from previous run)
-        if self.session_category:
-            for ch in self.session_category.text_channels:
-                if ch.topic and conversation_id in ch.topic:
-                    self.session_channels[conversation_id] = ch
-                    self.session_names[conversation_id] = project_name
-                    logger.info(f"Reconnected to existing channel #{ch.name}")
-                    return ch
+        async with self._channel_locks[conversation_id]:
+            # Double-check after acquiring lock
+            if conversation_id in self.session_channels:
+                return self.session_channels[conversation_id]
 
-        # Create new channel
-        try:
-            channel = await self.guild.create_text_channel(
-                name=channel_name,
-                category=self.session_category,
-                topic=f"Antigravity Session: {conversation_id}",
-            )
-            self.session_channels[conversation_id] = channel
-            self.session_names[conversation_id] = project_name
-            logger.info(f"Created channel #{channel_name}")
+            channel_name = f"{Config.CHANNEL_PREFIX}-{project_name}"
 
-            # Welcome embed
-            embed = discord.Embed(
-                title=f"🚀 {project_name}",
-                description=(
-                    f"Antigravity 세션 연결됨\n"
-                    f"Session: `{conversation_id}`"
-                ),
-                color=discord.Color.blue(),
-                timestamp=datetime.now(timezone.utc),
-            )
-            await channel.send(embed=embed)
-            return channel
+            # Check if channel already exists in category (from previous run)
+            if self.session_category:
+                for ch in self.session_category.text_channels:
+                    if ch.topic and conversation_id in ch.topic:
+                        self.session_channels[conversation_id] = ch
+                        self.session_names[conversation_id] = project_name
+                        logger.info(f"Reconnected to existing channel #{ch.name}")
+                        return ch
 
-        except discord.errors.Forbidden:
-            logger.error(f"No permission to create channel: {channel_name}")
-            return None
+            # Create new channel
+            try:
+                channel = await self.guild.create_text_channel(
+                    name=channel_name,
+                    category=self.session_category,
+                    topic=f"Antigravity Session: {conversation_id}",
+                )
+                self.session_channels[conversation_id] = channel
+                self.session_names[conversation_id] = project_name
+                logger.info(f"Created channel #{channel_name}")
+
+                # Welcome embed
+                embed = discord.Embed(
+                    title=f"🚀 {project_name}",
+                    description=(
+                        f"Antigravity 세션 연결됨\n"
+                        f"Session: `{conversation_id}`"
+                    ),
+                    color=discord.Color.blue(),
+                    timestamp=datetime.now(timezone.utc),
+                )
+                await channel.send(embed=embed)
+                return channel
+
+            except discord.errors.Forbidden:
+                logger.error(f"No permission to create channel: {channel_name}")
+                return None
 
     async def _process_events(self):
         """Main event processing loop."""
@@ -259,6 +278,8 @@ class GravityBot(commands.Bot):
             if channel:
                 if event.file_name == "task.md":
                     await self._send_task_update(channel, event)
+                elif event.file_name.endswith(".metadata.json"):
+                    await self._send_metadata_update(channel, event)
                 else:
                     await self._send_artifact_content(channel, event)
 
@@ -311,6 +332,42 @@ class GravityBot(commands.Bot):
                 await channel.send(chunk)
                 await asyncio.sleep(0.5)
 
+    async def _send_metadata_update(
+        self, channel: discord.TextChannel, event: BrainEvent
+    ):
+        """Send artifact metadata summary changes as compact embed."""
+        try:
+            meta = json.loads(event.content)
+        except json.JSONDecodeError:
+            return
+
+        summary = meta.get("summary", "")
+        artifact_type = meta.get("artifactType", "")
+        updated_at = meta.get("updatedAt", "")
+
+        if not summary:
+            return
+
+        # Map artifact types to emoji
+        type_emoji = {
+            "ARTIFACT_TYPE_TASK": "📋",
+            "ARTIFACT_TYPE_IMPLEMENTATION_PLAN": "📐",
+            "ARTIFACT_TYPE_WALKTHROUGH": "📝",
+            "ARTIFACT_TYPE_OTHER": "📄",
+        }
+        emoji = type_emoji.get(artifact_type, "📄")
+
+        # Artifact name from filename (strip .metadata.json)
+        artifact_name = event.file_name.replace(".metadata.json", "")
+
+        embed = discord.Embed(
+            description=f"{emoji} **{artifact_name}** 업데이트\n\n{summary[:500]}",
+            color=discord.Color.dark_teal(),
+            timestamp=datetime.now(timezone.utc),
+        )
+
+        await channel.send(embed=embed)
+
     @tasks.loop(minutes=5)
     async def session_cleanup_loop(self):
         """Periodically check for inactive sessions and archive their channels."""