zplugin,autoload: Support LOADED_PLUGINS defined by Zsh plugin standard

zplugin-autoload.zsh

@@ -1055,6 +1055,7 @@ ZPLGM[EXTENDED_GLOB]=""
     else
         (( quiet )) || print "Unregistering plugin $uspl2col"
         -zplg-unregister-plugin "$user" "$plugin"
+        LOADED_PLUGINS[${LOADED_PLUGINS[(i)$user/$plugin]}]=()  # Support Zsh plugin standard
         -zplg-clear-report-for "$user" "$plugin"
         (( quiet )) || print "Plugin's report saved to \$LASTREPORT"
     fi

zplugin.zsh

@@ -6,6 +6,7 @@
 #
 
 typeset -gaH ZPLG_REGISTERED_PLUGINS ZPLG_TASKS ZPLG_RUN
+typeset -ga LOADED_PLUGINS
 ZPLG_TASKS=( "<no-data>" )
 # Snippets loaded, url -> file name
 typeset -gAH ZPLGM ZPLG_REGISTERED_STATES ZPLG_SNIPPETS ZPLG_REPORTS ZPLG_ICE ZPLG_SICE
@@ -938,6 +939,9 @@ builtin setopt noaliases
         fi
     fi
 
+    # Support Zsh plugin standard
+    LOADED_PLUGINS+=( "$user/$plugin" )
+
     (( ${+ZPLG_ICE[atinit]} )) && { local __oldcd="$PWD"; builtin cd -q "${${${(M)user:#%}:+$plugin}:-${ZPLGM[PLUGINS_DIR]}/${user}---${plugin}}" && eval "${ZPLG_ICE[atinit]}"; builtin cd -q "$__oldcd"; }
 
     -zplg-load-plugin "$user" "$plugin" "$mode"