chore(zd): apply modelines and workflow conventions

* chore(zsh): apply standard modelines across plugins and libraries

* ci(workflows): enforce concurrency and permissions rules

---------

Co-authored-by: Salvydas Lukosius <ss-o@users.noreply.github.com>

Author: ss-o

.github/workflows/test-matrix.yml

@@ -1,5 +1,9 @@
 name: "ZUnit (Zsh matrix)"
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 on:
   schedule:
     - cron: "0 3 * * 3"

.github/workflows/test-native.yml

@@ -1,5 +1,9 @@
 name: "ZUnit (native)"
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
 

docker/utils.zsh

@@ -1,4 +1,6 @@
 #!/usr/bin/env zsh
+# -*- mode: zsh; sh-indentation: 2; indent-tabs-mode: nil; sh-basic-offset: 2; -*-
+# vim: ft=zsh sw=2 ts=2 et
 
 # Functions to wrap container setup and initialization.