feat(herdr): add plugin for herdr (#14079)

plugins/herdr/herdr.plugin.zsh

@@ -0,0 +1,68 @@
+# Aliases, helpers and completion for herdr (https://herdr.dev), the runtime for coding agents.
+
+# PROMPT
+# Defined before the herdr check so themes can reference it on machines without herdr.
+function herdr_prompt_info {
+  [[ "$HERDR_ENV" == 1 ]] || return
+  echo "${ZSH_THEME_HERDR_PROMPT_PREFIX}${HERDR_PANE_ID:gs/%/%%}${ZSH_THEME_HERDR_PROMPT_SUFFIX}"
+}
+
+if (( ! $+commands[herdr] )); then
+  return
+fi
+
+# ALIASES
+alias hrdr='herdr'
+alias hrdrst='herdr status'
+alias hrdrup='herdr update'
+alias hrdrsl='herdr session list'
+alias hrdrsa='herdr session attach'
+alias hrdrr='herdr --remote'
+alias hrdral='herdr agent list'
+alias hrdrwl='herdr workspace list'
+alias hrdrwc='herdr workspace create'
+alias hrdrwt='herdr worktree create'
+alias hrdrps='herdr pane split'
+alias hrdrrc='herdr server reload-config'
+
+# FUNCTIONS
+# Pick a session and attach to it, with fzf if available or a numbered menu otherwise.
+function hrdrs {
+  setopt localoptions extendedglob
+  local -a lines
+  lines=("${(@f)$(herdr session list 2>/dev/null)}")
+  lines=("${(@)lines%%[[:space:]]#[^[:space:]]#}")  # drop the socket column
+  if (( $#lines < 2 )); then
+    print "hrdrs: no herdr sessions found" >&2
+    return 1
+  fi
+
+  local choice
+  if (( $+commands[fzf] )); then
+    choice=$(print -l -- "${lines[@]}" | fzf --header-lines=1 --prompt='herdr session> ') || return
+  else
+    print -- "${lines[1]}"
+    local PS3="Attach to session: "
+    select choice in "${lines[@]:1}"; do
+      [[ -n "$choice" ]] && break
+    done
+  fi
+  [[ -n "$choice" ]] || return 1
+
+  herdr session attach "${${(z)choice}[1]}"
+}
+
+# COMPLETION
+# If the completion file doesn't exist yet, we need to autoload it and
+# bind it to `herdr`. Otherwise, compinit will have already done that.
+if [[ ! -f "$ZSH_CACHE_DIR/completions/_herdr" ]]; then
+  typeset -g -A _comps
+  autoload -Uz _herdr
+  _comps[herdr]=_herdr
+fi
+
+zmodload -F zsh/files b:zf_mv
+() {
+  local TMPPREFIX="$ZSH_CACHE_DIR/completions/_herdr"
+  zf_mv -f -- =( herdr completion zsh < /dev/null 2> /dev/null ) "$TMPPREFIX"
+} &|