Move custom helm bindings to top-level db/run-init

Configuring custom key bindings via use-package's :map keyword does seem to
install autoloads for the bound functions into the main helm package.  I.e.,
when binding `db/play-radio-stations' to # in `helm-command-map' via :map,
use-package seems to install an autoload for `db/play-radio-stations' that
requires `helm', instead of the correct `db-music' package.  Additionally,
defining key bindings somewhere in the init file is hard to manage, and they are
thus now collected with other key bindings in `db/run-init'.

init.el

@@ -112,8 +112,6 @@
     (with-demoted-errors "Cannot activate mode: %s"
       (funcall mode +1)))
 
-  (require 'helm)
-
   (unless on-windows
     (with-demoted-errors "Cannot load `pdf-tools’: %s"
       (pdf-tools-install)))
@@ -218,6 +216,12 @@
   (bind-key [remap fill-paragraph] #'endless/fill-or-unfill)
   (unbind-key "C-x C-c" global-map)
 
+  ;; Custom helm bindings
+
+  (require 'helm)
+  (bind-key "#" #'db/play-radio-stations helm-command-map)
+  (bind-key "P" #'helm-pages helm-command-map)
+
   ;; Overwrite certain keybindings only if packages are avilable
 
   (when (package-installed-p 'counsel)
@@ -1883,9 +1887,6 @@ With given ARG, display files in `db/important-document-path’."
 (use-package helm
   :ensure t
   :diminish helm-mode
-  :bind (:map helm-command-map
-              ("#" . db/play-radio-stations)
-              ("P" . helm-pages))
   :init (setq helm-command-prefix-key "C-c h"
               helm-input-idle-delay 0.0
               helm-buffers-fuzzy-matching t