feat(container): add container plugin with completions and aliases

- add plugin file: plugins/container/container.plugin.zsh
- add completions file: plugins/container/completions/_container
- add README for plugin
- justify aliases and include usage notes in README

plugins/container/container.plugin.zsh

@@ -0,0 +1,88 @@
+# Container plugin for Apple's container tool
+# https://github.com/apple/container
+
+# Aliases for common container commands
+alias cb='container build'
+alias ccr='container create'
+alias cst='container start'
+alias csp='container stop'
+alias ck='container kill'
+alias cdl='container delete'
+alias crm='container delete'
+alias cls='container list'
+alias clsa='container list -a'
+alias cex='container exec'
+alias cexit='container exec -it'
+alias clo='container logs'
+alias clof='container logs -f'
+alias cin='container inspect'
+alias cr='container run'
+alias crit='container run -it'
+alias crd='container run -d'
+
+# Image management aliases
+alias cils='container image list'
+alias cipl='container image pull'
+alias cips='container image push'
+alias cisv='container image save'
+alias cild='container image load'
+alias citg='container image tag'
+alias cirm='container image delete'
+alias cipr='container image prune'
+alias ciin='container image inspect'
+
+# Builder management aliases
+alias cbst='container builder start'
+alias cbsp='container builder stop'
+alias cbss='container builder status'
+alias cbrm='container builder delete'
+
+# Network management aliases (macOS 26+)
+alias cncr='container network create'
+alias cnrm='container network delete'
+alias cnls='container network list'
+alias cnin='container network inspect'
+
+# Volume management aliases
+alias cvcr='container volume create'
+alias cvrm='container volume delete'
+alias cvls='container volume list'
+alias cvin='container volume inspect'
+
+# Registry management aliases
+alias crli='container registry login'
+alias crlo='container registry logout'
+
+# System management aliases
+alias csst='container system start'
+alias cssp='container system stop'
+alias csss='container system status'
+alias cslo='container system logs'
+alias cske='container system kernel set'
+alias cspl='container system property list'
+alias cspg='container system property get'
+alias csps='container system property set'
+alias cspc='container system property clear'
+
+# Check if container command is available
+if (( ! $+commands[container] )); then
+  return
+fi
+
+# Standardized $0 handling
+# https://zdharma-continuum.github.io/Zsh-100-Commits-Club/Zsh-Plugin-Standard.html
+0="${${ZERO:-${0:#$ZSH_ARGZERO}}:-${(%):-%N}}"
+0="${${(M)0:#/*}:-$PWD/$0}"
+
+# If the completion file doesn't exist yet, we need to autoload it and
+# bind it to `container`. Otherwise, compinit will have already done that.
+if [[ ! -f "$ZSH_CACHE_DIR/completions/_container" ]]; then
+  typeset -g -A _comps
+  autoload -Uz _container
+  _comps[container]=_container
+fi
+
+{
+  # Copy the custom completion file to cache
+  command cp "${0:h}/completions/_container" "$ZSH_CACHE_DIR/completions/_container"
+} &|