docs(ops): record 103 goosed native migration and add migrate tooling

Document the completed Docker-to-native goosed pool cutover on 103, add the production migrate script with backup/rollback paths, and extend local native pool soak/metrics helpers used as migration gates.

Co-authored-by: Cursor <cursoragent@cursor.com>

.env.example

@@ -6,6 +6,12 @@
 #
 # 后端代理（server.mjs / vite dev proxy 共用）
 TKMIND_API_TARGET=https://127.0.0.1:18006
+# Native dual pool (local simulation): bash scripts/install-local-goosed-pool.sh
+# TKMIND_API_TARGET_1=https://127.0.0.1:18007
+# TKMIND_API_TARGETS=https://127.0.0.1:18006,https://127.0.0.1:18007
+# GOOSED_NATIVE_POOL_PORTS=18006,18007
+# GOOSED_RUNTIME=native   # runtime-worker-metrics.mjs; auto detects when no docker pool
+# Soak: node scripts/soak-local-goosed-pool.mjs --minutes 30 --interval 60
 TKMIND_SERVER__SECRET_KEY=local-dev-secret
 H5_PORT=8081
 # Vite UI 预览用 5173；Agent 交付的 MindSpace 公开页 + Page Data API 走 Portal（8081）。