They were only disabled in the reply tool, because their wikitext
markup doesn't work when indented. This is not a concern in the new
topic tool.
Rename our sequences that display the wikitext warning to avoid these
items showing up in the command help dialog, and remove overrides for
global ve.ui.commandHelpRegistry. (As a result, the dialog now lists
the blockquote command, which was previously missing even though it
was enabled, but only with the 'Ctrl+8' shortcut and not 'Type ":"'.)
Also remove filtering rules for external paste.
Bug: T311653
Change-Id: I4557c376fcf099d81e91ae5c2b18301d97921180
Load 'ext.visualEditor.mwsignature' (which implements VE's existing
handling for signatures), then subclass and override a bunch of things
in order to:
* Replace the context menu with a note that you don't need to type the
signature when commenting using the reply widget
* Override the sequence/command to insert signature so that it selects
it afterwards and thus displays the context menu
* Treat signatures as signature nodes when switching from wikitext,
instead of the normal pre-save transform turning them into regular
links and text
Bug: T255738
Change-Id: Icb542451c2307ab51e56bd627804096c7b5552c8
