fix(collector): 기능 누락 3건 수정 — Discord 명령어/채팅/등록 중계

Gap 1: Discord→Extension 명령어 깨짐
  - bot.py: _write_command() 래퍼 — gateway.push_command()도 호출
  - main.py: bot.gateway 연결
  - 슬래시 명령어 + on_message 모두 _write_command 사용

Gap 2: Chat snapshot 미전달
  - collector.py: _forward_chat_snapshots_loop 추가

Gap 3: Session registration 미전달
  - collector.py: _forward_registrations_loop 추가

collector.py

@@ -50,6 +50,8 @@ class CollectorBridge:
             self._forward_pending_loop(),
             self._poll_responses_loop(),
             self._poll_commands_loop(),
+            self._forward_chat_snapshots_loop(),
+            self._forward_registrations_loop(),
         ]
         if self.event_queue:
             tasks.append(self._forward_events_loop())
@@ -132,6 +134,56 @@ class CollectorBridge:
 
             await asyncio.sleep(self._poll_interval)
 
+    # ─── Forward chat snapshots → Gateway ───
+
+    async def _forward_chat_snapshots_loop(self):
+        """Forward chat_snapshots/ from Extension to Gateway."""
+        while self._running:
+            try:
+                snap_dir = self.local.bridge_dir / "chat_snapshots"
+                if snap_dir.exists():
+                    for f in snap_dir.glob("*.json"):
+                        try:
+                            data = json.loads(f.read_text(encoding="utf-8-sig"))
+                            project = data.get("project_name", self.project_name)
+                            content = data.get("content", "")
+                            if content:
+                                self.remote.send_chat(project, content)
+                                logger.info(f"[COLLECTOR] → Gateway: chat snapshot len={len(content)}")
+                            f.unlink()  # Cleanup after forwarding
+                        except (json.JSONDecodeError, OSError) as e:
+                            logger.warning(f"[COLLECTOR] bad chat snapshot {f.name}: {e}")
+            except Exception as e:
+                logger.error(f"[COLLECTOR] forward_chat_snapshots error: {e}")
+
+            await asyncio.sleep(self._poll_interval)
+
+    # ─── Forward session registrations → Gateway ───
+
+    async def _forward_registrations_loop(self):
+        """Forward register/ files from Extension to Gateway."""
+        forwarded_regs: set[str] = set()
+        while self._running:
+            try:
+                register_dir = self.local.bridge_dir / "register"
+                if register_dir.exists():
+                    for f in register_dir.glob("*.json"):
+                        if f.name in forwarded_regs:
+                            continue
+                        try:
+                            data = json.loads(f.read_text(encoding="utf-8-sig"))
+                            conv_id = data.get("conversation_id", "")
+                            project = data.get("project_name", "")
+                            if conv_id and project:
+                                self.remote.register_session(conv_id, project)
+                                forwarded_regs.add(f.name)
+                                logger.info(f"[COLLECTOR] → Gateway: register {conv_id[:8]} → {project}")
+                        except (json.JSONDecodeError, OSError) as e:
+                            logger.warning(f"[COLLECTOR] bad register {f.name}: {e}")
+            except Exception as e:
+                logger.error(f"[COLLECTOR] forward_registrations error: {e}")
+
+            await asyncio.sleep(self._poll_interval * 3)  # Less frequent
     # ─── Forward brain events → Gateway ───
 
     async def _forward_events_loop(self):