Add per-node translation management: list, edit, destroy, compare

Replaces the old locale-switch-and-edit-the-same-screen workflow,
which conflated presentation locale with content locale and let an
editor silently drift into editing the wrong language with no
persistent signal that anything had changed. Non-default-locale
content now has its own explicit routes and screens, never sharing
a route param with the ambient chrome locale.

- PageTranslationsController: index/show/edit/update/destroy,
  scoped to Page.non_default_locales; update handles first-time
  creation too, so there's no separate new/create step.
- Reads go through the actual PageTranslation row
  (Page#translation_summary), never through the Globalize
  fallback-bearing accessor -- fallback is correct for public
  rendering but wrong for editing, where a missing translation
  needs to look empty, not borrowed from another locale.
- Translations ride on the page's own draft/head cycle; no
  independent publish state.
- nodes#show gains a Translations section (per-locale Lock+Edit /
  Create+Lock, Destroy, a link into the read-only Compare view) and
  a locale indicator on its own default-locale content; nodes#edit,
  nodes#update, and nodes#autosave are pinned to the default locale
  via Globalize.with_locale regardless of the ambient route locale.
- nodes#show no longer double-loads the node or calls wipe_draft!
  on every view (see previous commit for why that's now safe).
- .preview_link_row is renamed .aligned_action_row now that it has
  a second real consumer.

1 files changed, 9 insertions, 3 deletions

diff --git a/app/controllers/nodes_controller.rb b/app/controllers/nodes_controller.rb
index c1468be..249602d 100644
--- a/app/controllers/nodes_controller.rb
+++ b/app/controllers/nodes_controller.rb
@@ -16,6 +16,8 @@ class NodesController < ApplicationController
                               :revert
                             ]
 
+  around_action :pin_to_default_locale, :only => [:show, :edit, :update, :autosave]
+
   def index
     @nodes = Node.root.descendants.includes(:head, :draft)
       .order('id DESC')
@@ -59,9 +61,9 @@ class NodesController < ApplicationController
   end
 
   def show
-    node = Node.find(params[:id])
-    node.wipe_draft!
-    @page = node.draft || node.head
+    @page = @node.draft || @node.head
+    @default_translation = @page.translations.find_by(:locale => I18n.default_locale)
+    @translations = @page.translation_summary
   end
 
   def edit
@@ -248,6 +250,10 @@ class NodesController < ApplicationController
       end
     end
 
+    def pin_to_default_locale
+      Globalize.with_locale(I18n.default_locale) { yield }
+    end
+
     def descendant_counts_for(ordered_with_level)
       counts = Hash.new(0)
       stack = [] # [node, level, index]