Use proper directory name also for exit status temp

dotfiles/bashum/head.bashrc

 #!/bin/bash
 
-mkdir -p /var/tmp/bash-rv
+mkdir -p /var/tmp/bashum-rv
 
 BASHUM_TASK_CTX=false
 BASHUM_BMO_NAG=false

dotfiles/bashum/main.bashrc

     xo | pad4 | xii
 }
 
-RV_TMP="/tmp/bash-rv"
-mkdir -p "$RV_TMP"
+BASHUM__RV_TMP="/tmp/bashum-rv"
+mkdir -p "$BASHUM__RV_TMP"
 
 ### ...... ###
 ### OTHERS ###

dotfiles/bashum/post.bashrc

     local rvfile        # path to return value cache file
     local lastrv        # actual last return value
     local do_rm         # true if we should remove the cache
-    rvfile="$RV_TMP/$$.lastrv"
+    rvfile="$BASHUM__RV_TMP/$$.lastrv"
     lastrv="$(cat "$rvfile")"
     do_rm=false
     test "$1" == "-r" && do_rm=true
 }
 
 __bashum__save_rv() {
-    local rvfile="$RV_TMP/$$.lastrv"
+    local rvfile="$BASHUM__RV_TMP/$$.lastrv"
     [ -w "${rvfile%/*}" ] && echo "$1" > "$rvfile"
 }