feat(Session 241): Add scale-out MCP tools

Position Exit Management System support:
- scale_out_status: Service status and statistics
- scale_out_pending: Positions awaiting scale-out
- scale_out_stats: Execution statistics
- scale_out_set_dry_run: Toggle dry-run mode

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/server.py

@@ -385,6 +385,33 @@ async def list_tools() -> list[Tool]:
             description="Find duplicate pending orders (same instrument + rate + direction). Returns order IDs to cancel.",
             inputSchema={"type": "object", "properties": {}, "required": []},
         ),
+        # === SCALE-OUT (Session 241: Position Exit Management) ===
+        Tool(
+            name="scale_out_status",
+            description="Get scale-out monitor service status (running, dry-run mode, statistics)",
+            inputSchema={"type": "object", "properties": {}, "required": []},
+        ),
+        Tool(
+            name="scale_out_pending",
+            description="Get positions pending scale-out (haven't had 50% partial close executed yet)",
+            inputSchema={"type": "object", "properties": {}, "required": []},
+        ),
+        Tool(
+            name="scale_out_stats",
+            description="Get scale-out statistics (total, executed, pending, P/L locked)",
+            inputSchema={"type": "object", "properties": {}, "required": []},
+        ),
+        Tool(
+            name="scale_out_set_dry_run",
+            description="Enable or disable scale-out dry-run mode. In dry-run, scale-outs are logged but not executed.",
+            inputSchema={
+                "type": "object",
+                "properties": {
+                    "dry_run": {"type": "boolean", "description": "True to enable dry-run (log only), False to enable live execution"},
+                },
+                "required": ["dry_run"],
+            },
+        ),
         # === CONTAINER OPERATIONS ===
         Tool(
             name="container_logs",
@@ -578,6 +605,15 @@ async def call_tool(name: str, arguments: dict[str, Any]) -> list[TextContent]:
                 result = await api_post("/api/trade/orders/cancel-bulk", {"order_ids": order_ids})
         case "find_duplicate_orders":
             result = await api_get("/api/trade/orders/duplicates")
+        # === SCALE-OUT (Session 241) ===
+        case "scale_out_status":
+            result = await api_get("/api/trade/scale-out/status")
+        case "scale_out_pending":
+            result = await api_get("/api/trade/scale-out/pending")
+        case "scale_out_stats":
+            result = await api_get("/api/trade/scale-out/stats")
+        case "scale_out_set_dry_run":
+            result = await api_post("/api/trade/scale-out/dry-run", {"dry_run": arguments["dry_run"]})
         # === CONTAINER OPERATIONS ===
         case "container_logs":
             params = [f"container={arguments['container']}"]