Arregla bug de trap RETURN en pkgsync.sh y quita mención stale a DavMail

trap RETURN persiste entre retornos de función en bash, no solo el de la
función que lo puso: al volver de compute_diff/cmd_push/cmd_audit hacia
arriba en la pila, volvía a dispararse sobre un $work ya fuera de scope
('work: variable sin asignar' bajo set -u). Cambiado a rm -rf explícito en
cada punto de salida.

DavMail se desinstaló del sistema; ya no debía aparecer en la lista de apps.

README.md

@@ -74,7 +74,7 @@ privado), nombre y email de git. Después, sin más intervención:
 
 Comunes (`shared/packages-common.sh`): zsh+starship+CLI moderno, git+base-devel,
 Podman, nodejs/python/rustup, Bitwarden, DBeaver, Obsidian, GIMP, Syncthing,
-Remmina+FreeRDP, Apostrophe, guvcview, KVIrc, Zen Browser, VSCode, DavMail,
+Remmina+FreeRDP, Apostrophe, guvcview, KVIrc, Zen Browser, VSCode,
 Betterbird, OnlyOffice, Spotify, ungoogled-chromium, Karere, HelpWire (vía
 `.deb`→`debtap`). GNOME añade gnome-calculator/tweaks; KDE añade
 kcalc/ark/spectacle/kdeconnect/kinfocenter.

pkgsync/pkgsync.sh

@@ -183,7 +183,6 @@ write_group_file() {
 compute_diff() {
   local work
   work="$(mktemp -d)"
-  trap 'rm -rf "$work"' RETURN
 
   { declared_array PACMAN_COMMON; declared_array AUR_COMMON; printf '%s\n' "${CRITICAL_PACKAGES[@]}"; } | sort -u >"$work/declared_arch"
   declared_array FLATPAK_COMMON | sort -u >"$work/declared_flatpak"
@@ -195,6 +194,8 @@ compute_diff() {
   mapfile -t TO_REVIEW_REMOVE_ARCH < <(comm -13 "$work/declared_arch" "$work/installed_arch" | comm -23 - "$work/overrides")
   mapfile -t TO_INSTALL_FLATPAK < <(comm -23 "$work/declared_flatpak" "$work/installed_flatpak" | comm -23 - "$work/overrides")
   mapfile -t TO_REVIEW_REMOVE_FLATPAK < <(comm -13 "$work/declared_flatpak" "$work/installed_flatpak" | comm -23 - "$work/overrides")
+
+  rm -rf "$work"
 }
 
 print_list() {
@@ -283,7 +284,6 @@ cmd_push() {
 
   local work
   work="$(mktemp -d)"
-  trap 'rm -rf "$work"' RETURN
 
   installed_pacman_native | sort -u >"$work/inst_native"
   installed_pacman_foreign | sort -u >"$work/inst_foreign"
@@ -314,6 +314,7 @@ cmd_push() {
   patch_array_file "$pc" AUR_COMMON "$remove_aur" "$add_aur"
   patch_array_file "$pc" FLATPAK_COMMON "$remove_flatpak" "$add_flatpak"
 
+  rm -rf "$work"
   write_group_file
 
   cd "$REPO_DIR" || return 0
@@ -409,7 +410,6 @@ cmd_incoming() {
 cmd_audit() {
   local work
   work="$(mktemp -d)"
-  trap 'rm -rf "$work"' RETURN
 
   { declared_array PACMAN_COMMON; declared_array AUR_COMMON; printf '%s\n' "${CRITICAL_PACKAGES[@]}"; overrides_packages; } | sort -u >"$work/declared_arch"
   { declared_array FLATPAK_COMMON; overrides_packages; } | sort -u >"$work/declared_flatpak"
@@ -430,6 +430,8 @@ cmd_audit() {
   echo "(nota: los paquetes específicos de KDE/GNOME hardcodeados en <de>/setup.sh"
   echo " -- plasma-desktop, sddm, temas AUR, etc. -- siempre van a salir aquí: no"
   echo " viven en los arrays de packages-common.sh por diseño, no es drift real)"
+
+  rm -rf "$work"
 }
 
 usage() {