refactor(cli): group theme browser files

tools/theme-browser/preview-worker.zsh

@@ -0,0 +1,88 @@
+# Invoked only by preview.zsh in a fresh zsh -df process. Themes and hooks
+# are intentionally sourced/run at top level (not inside a setup function).
+emulate -R zsh
+if [[ $1 == --supervise ]]; then
+  # This process is the private PTY's session leader. Keep the actual worker's
+  # standard descriptors non-TTY, and report its status outside theme state.
+  typeset -r _omz_preview_tmp=$2
+  shift 2
+  unsetopt monitor
+  command "$commands[zsh]" -df "${0:A}" "$@" \
+    < /dev/null > "$_omz_preview_tmp/output" 2>&1
+  print -r -- $? > "$_omz_preview_tmp/result"
+  exit
+fi
+typeset -r _omz_preview_root=$1 _omz_preview_theme=$2 _omz_preview_status=$3
+export ZSH=${ZSH:-$_omz_preview_root}
+ZSH_THEME=$4
+ZSH_CUSTOM=$5
+fpath=("$_omz_preview_root/functions" $fpath)
+autoload -Uz colors add-zsh-hook vcs_info
+colors
+setopt prompt_subst prompt_percent
+zstyle ':omz:alpha:lib:git' async-prompt no
+ZSH_THEME_GIT_PROMPT_PREFIX='git:('
+ZSH_THEME_GIT_PROMPT_SUFFIX=')'
+ZSH_THEME_GIT_PROMPT_DIRTY='*'
+ZSH_THEME_GIT_PROMPT_CLEAN=''
+ZSH_THEME_RUBY_PROMPT_PREFIX='('
+ZSH_THEME_RUBY_PROMPT_SUFFIX=')'
+source "$_omz_preview_root/lib/git.zsh"
+source "$_omz_preview_root/lib/vcs_info.zsh"
+source "$_omz_preview_root/lib/bzr.zsh"
+source "$_omz_preview_root/lib/nvm.zsh"
+source "$_omz_preview_root/lib/prompt_info_functions.zsh"
+source "$_omz_preview_root/lib/spectrum.zsh"
+# Check syntax before accepting a final false conditional as a successful load.
+# This subprocess shares the worker's execution deadline and process group.
+command "$commands[zsh]" -dfn "$_omz_preview_theme" || {
+  print -u2 -r -- 'theme preview: theme syntax check failed'
+  exit 1
+}
+# Keep zsh's PROMPT/PS1 and RPROMPT/RPS1 aliases intact (dieter sets RPS1).
+PROMPT=''
+RPROMPT=''
+source "$_omz_preview_theme"
+typeset -i _omz_preview_load_status=$?
+# Status 1 may just be a final conditional; require an initialized prompt below.
+# Higher statuses include syntax/runtime errors and missing commands.
+if (( _omz_preview_load_status > 1 )); then
+  print -u2 -r -- "theme preview: theme could not be loaded (exit $_omz_preview_load_status)"
+  exit 1
+fi
+
+function _omz_preview_set_status { return "$_omz_preview_status" }
+typeset -i _omz_preview_hook_status=0
+if (( $+functions[precmd] )); then
+  _omz_preview_set_status
+  precmd
+  _omz_preview_hook_status=$?
+  if (( _omz_preview_hook_status )); then
+    print -u2 -r -- "theme preview: precmd failed (exit $_omz_preview_hook_status); remaining hooks skipped"
+  fi
+fi
+for _omz_preview_hook in "${precmd_functions[@]}"; do
+  (( _omz_preview_hook_status )) && break
+  if (( $+functions[$_omz_preview_hook] )); then
+    _omz_preview_set_status
+    "$_omz_preview_hook"
+    _omz_preview_hook_status=$?
+    if (( _omz_preview_hook_status )); then
+      print -u2 -r -- "theme preview: precmd hook $_omz_preview_hook failed (exit $_omz_preview_hook_status); remaining hooks skipped"
+    fi
+  fi
+done
+if (( _omz_preview_load_status )) && [[ -z $PROMPT && -z $RPROMPT ]]; then
+  print -u2 -r -- "theme preview: theme did not initialize a prompt (load exit $_omz_preview_load_status)"
+  exit 1
+fi
+# Native prompt expansion handles PROMPT_SUBST once, followed by percent escapes.
+# An explicit (e) pass here would re-execute literal substitutions from helpers.
+print -r -- "Left prompt (status $_omz_preview_status):"
+_omz_preview_set_status
+print -Pr -- "${PROMPT-}"
+print -r -- 'Right prompt (shown separately):'
+_omz_preview_set_status
+print -Pr -- "${RPROMPT-}"
+(( _omz_preview_hook_status )) && exit 1
+exit 42