feat(view): DVIEW twists the view about its line of sight

DVIEW (alias DV) offers TWist and Undo. TWist rolls the active view
or viewport camera to the typed angle; Undo steps back through the
twists made in the session. The new alias reaches existing profiles
through the alias migration table.

Refs #638

Co-Authored-By: Claude Opus 5.5 <[email protected]>

assets/ocad.pgp

@@ -155,6 +155,7 @@ SHA,      *SHADEMODE
 COL,      *COLOR
 DR,       *DRAWORDER
 DS,       *DSETTINGS
+DV,       *DVIEW
 LT,       *LINETYPE
 LTS,      *LTSCALE
 OS,       *OSNAP