fix: portal stability, session list DB fallback, and UX polish

- Free stale Memind listeners on 8081 before startup and exit cleanly on EADDRINUSE
- Backfill owned sessions missing from Goose via h5_conversation_messages summaries
- Strip Memind task orchestration prefixes from user-facing chat text
- Repair missing public docx links before release MindSpace link checks

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

scripts/release-portal-runtime-prod.sh

@@ -555,11 +555,15 @@ if [[ "${portal_code}" != "200" ]]; then
 fi
 
 if [[ "${ALLOW_MINDSPACE_PUBLIC_LINK_ISSUES:-0}" != "1" && -d "${APP_DIR}/MindSpace" && -f "${APP_DIR}/scripts/check-mindspace-public-links.mjs" ]]; then
-  say "检查 MindSpace 公开页相对链接"
+  say "修复 MindSpace 公开页缺失 docx 下载"
   node_bin="/opt/homebrew/opt/node@24/bin/node"
   if [[ ! -x "${node_bin}" ]]; then
     node_bin="$(command -v node)"
   fi
+  if [[ -f "${APP_DIR}/scripts/repair-mindspace-public-downloads.mjs" ]]; then
+    "${node_bin}" "${APP_DIR}/scripts/repair-mindspace-public-downloads.mjs" --root "${APP_DIR}/MindSpace" || true
+  fi
+  say "检查 MindSpace 公开页相对链接"
   if ! "${node_bin}" "${APP_DIR}/scripts/check-mindspace-public-links.mjs" --root "${APP_DIR}/MindSpace" --downloads-only; then
     echo "MindSpace public link check failed: broken relative download/asset links under public/*.html" >&2
     echo "Set ALLOW_MINDSPACE_PUBLIC_LINK_ISSUES=1 only if you accept shipping with known broken links." >&2