docs: expand libtinfo troubleshooting; add scripts/env-no-ld.sh

- README: deactivate may not clear LD_LIBRARY_PATH; unset, /usr/bin/vi, diagnostics
- scripts/env-no-ld.sh: run commands without LD_LIBRARY_PATH for vi/bash
- run.sh: include in commit if changed (verify diff)

Made-with: Cursor

scripts/env-no-ld.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+# LD_LIBRARY_PATH 없이 명령 실행 (conda libtinfo 때문에 vi/bash 등이 경고 낼 때)
+# 사용: ./scripts/env-no-ld.sh vi run.sh
+#       ./scripts/env-no-ld.sh bash -c 'echo ok'
+exec env -u LD_LIBRARY_PATH "$@"