feat: add script catalog and -h help for all dotfile scripts

Introduce ff script -h with auto descriptions, shared help.sh, and usage flags across script/*.sh.

Co-authored-by: Cursor <cursoragent@cursor.com>

script/nvm-install.sh

@@ -1,9 +1,31 @@
 #!/bin/bash
+# 安装 fnm（Node 版本管理）并 reload fish 配置
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# shellcheck disable=SC1091
+source "$SCRIPT_DIR/common/help.sh"
+
+usage() {
+    cat <<'EOF'
+用法: nvm-install
+
+通过 fnm 官方安装脚本安装 Fast Node Manager，并执行 ff reload。
+
+选项:
+  -h, --help  显示此帮助
+
+说明: 本仓库 fish 配置中 nvm 别名指向 fnm。
+EOF
+}
+
+dotfile_help_requested "${1:-}" && dotfile_show_help
+
+set -euo pipefail
 
-# https://github.com/Schniz/fnm
 curl -fsSL https://fnm.vercel.app/install | bash
 
-ff reload
-
-# after install node
-# corepack enable pnpm
+if command -v ff &>/dev/null; then
+    ff reload
+elif command -v fish &>/dev/null; then
+    fish -c "source ~/.config/fish/config.fish"
+fi