Initial: luochen570-cli Docker image with zsh+zinit+NvChad+CLI tools

- Alpine-based Docker image
- zsh + zinit + Powerlevel10k
- zsh-autosuggestions, fast-syntax-highlighting
- CLI tools: yazi, eza, fzf, duf, ncdu, bat, tree, tmux
- NvChad (neovim IDE config)
- Weekly Gitea Actions build workflow (multi-arch)
- Gitea Container Registry publishing

.dockerignore

@@ -0,0 +1,17 @@
+# Git
+.git/
+.gitignore
+
+# Docker
+Dockerfile
+.dockerignore
+README.md
+.gitea/
+
+# macOS
+.DS_Store
+
+# Editor
+*.swp
+*.swo
+*~