Move emacs/electric-indent to emacs/electric

This module will later be expanded to customize more of electric's
functionality.

modules/emacs/electric/config.el

@@ -0,0 +1,19 @@
+;;; emacs/electric/config.el -*- lexical-binding: t; -*-
+
+;; Smarter, keyword-based electric-indent
+
+(defvar-local +electric-indent-words '()
+  "The list of electric words. Typing these will trigger reindentation of the
+current line.")
+
+;;
+(after! electric
+  (setq-default electric-indent-chars '(?\n ?\^?))
+
+  (defun +electric-indent|char (_c)
+    (when (and (eolp) +electric-indent-words)
+      (save-excursion
+        (backward-word)
+        (looking-at-p (concat "\\<" (regexp-opt +electric-indent-words))))))
+  (add-to-list 'electric-indent-functions #'+electric-indent|char nil #'eq))
+