* lisp/emulation/: Use lexical-binding

* lisp/emulation/: Use lexical-binding

* lisp/emulation/cua-base.el: Use lexical-binding.
Remove redundant `:group` arguments.
(cua-mode): Don't use `:require` since the autoload on `define-minor-mode`
takes care of loading the mode when custom-setting it.

* lisp/emulation/cua-gmrk.el: Use lexical-binding.
(cua--copy-rectangle-to-global-mark): Remove unused var `src-buf`.

* lisp/emulation/edt-mapper.el: Use lexical-binding.

* lisp/emulation/edt.el: Use lexical-binding.
Remove redundant `:group` arguments.
(edt-with-position): Allow `top`, `left`, and `far` to be left unused
in `body`.

* lisp/emulation/keypad.el: Use lexical-binding.

* lisp/emulation/viper-cmd.el: Move `provide` to the end.
(viper-read-string-with-history): Strength reduce `eval` to `symbol-value`.

* lisp/emulation/viper-ex.el: Use lexical-binding.
Remove redundant `:group` arguments.
Move `provide` to the end.

* lisp/emulation/viper-init.el: Use lexical-binding.

* lisp/emulation/viper-keym.el (viper-toggle-key): Use `dolist`.
(viper-insert-diehard-map): Use `string`.
(viper-modify-major-mode): Use `alist-get` and `setf`.

* lisp/emulation/viper-macs.el (viper-ex-work-buf):
Move `provide` to the end.
(viper-record-kbd-macro): Strength reduce `eval` to `symbol-value`.
(viper-describe-kbd-macros): Return value is not significant.
(viper-keyseq-is-a-possible-macro): Use `seq-some`.
(viper-common-seq-prefix): Use `seq-every-p`.

* lisp/emulation/viper-mous.el: Use lexical-binding.
Remove redundant `:group` arguments.
Move `provide` to the end.
(viper-remember-current-frame): Accept arbitrary ignored args.
(viper-parse-mouse-key): Strength reduce `eval` to `symbol-value`.
Remove unused var `key-spec`.
(viper-bind-mouse-search-key, viper-bind-mouse-insert-key):
Apply de Morgan.

* lisp/emulation/viper-util.el: Move `provide` to the end.
(viper-move-marker-locally, viper-push-onto-ring, viper-save-setting):
Strength reduce `eval` to `symbol-value`.
(viper-event-vector-p, viper-char-symbol-sequence-p, viper-char-array-p):
Use `seq-every-p`.

* lisp/emulation/viper.el (viper-non-hook-settings): Eta-reduce use of
`viper-remember-current-frame`.