fix: guard success messages on command exit status

- Source x-path instead of capturing empty stdout via command substitution
- Validate --dry-run argument in cleanup script, reject unknown flags
- Gate success messages on preceding command's exit status with &&
- Applies to dfm (fmt, reset_nvim, shfmt) and install scripts
  (fonts, gh-extensions, python-packages, shellspec, z)

scripts/cleanup-old-version-managers.sh

@@ -12,7 +12,15 @@ fi
 # shellcheck source=shared.sh
 source "$DOTFILES/config/shared.sh"
 
-DRY_RUN="${1:-}"
+DRY_RUN=""
+if [[ $# -gt 0 ]]; then
+  if [[ "$1" = "--dry-run" ]]; then
+    DRY_RUN="--dry-run"
+  else
+    echo "Usage: $0 [--dry-run]" >&2
+    exit 1
+  fi
+fi
 
 remove_dir()
 {

scripts/install-fonts.sh

@@ -51,8 +51,9 @@ install_fonts()
 {
   msgr run "Starting to install NerdFonts..."
   # shellcheck disable=SC2048,SC2086
-  ./install.sh -q -s ${fonts[*]}
-  msgr run_done "Done"
+  # shellcheck disable=SC2086
+  ./install.sh -q -s ${fonts[*]} \
+    && msgr run_done "Done"
   return 0
 }
 

scripts/install-gh-extensions.sh

@@ -51,8 +51,8 @@ install_extensions()
 # Install all GitHub CLI extensions
 main()
 {
-  install_extensions
-  msgr run_done "Done"
+  install_extensions \
+    && msgr run_done "Done"
   return 0
 }
 

scripts/install-python-packages.sh

@@ -35,5 +35,5 @@ install_libraries()
   return 0
 }
 
-install_libraries
-msgr yay "Python library installations complete"
+install_libraries \
+  && msgr yay "Python library installations complete"

scripts/install-shellspec.sh

@@ -23,8 +23,8 @@ install_shellspec()
   fi
 
   msgr run "Running make install..."
-  make -C "$SHELLSPEC_CACHE" install PREFIX="$HOME/.local"
-  msgr run_done "shellspec $version installed to $HOME/.local/bin/shellspec"
+  make -C "$SHELLSPEC_CACHE" install PREFIX="$HOME/.local" \
+    && msgr run_done "shellspec $version installed to $HOME/.local/bin/shellspec"
   return 0
 }
 

scripts/install-z.sh

@@ -15,8 +15,8 @@ clone_z_repo()
   local bin_path=$2
 
   if [[ ! -d "$bin_path" ]]; then
-    git clone "$git_path" "$bin_path"
-    msgr run_done "z installed at $bin_path"
+    git clone "$git_path" "$bin_path" \
+      && msgr run_done "z installed at $bin_path"
   else
     msgr ok "z ($bin_path/) already installed"
   fi