Let the phone delete a host, and move or remove a group

The desktop gained three things the phone did not follow: moving a group to
another vault, the second question asking whether a group's deletion takes its
hosts with it, and — since long before either — deleting a host at all. What
that left was a head whose v3 + can fill a keychain and whose editors can
correct one, with no way to empty either.

The commands could not simply be bound. DeleteGroup and MoveGroup aim at
GroupTarget, which is the selected card or the open group, and the phone has
neither: its list draws headings, and a heading's selection deliberately bounces
back to the host. Called bare on that head they would have returned having done
nothing — a DELETE that appears to have been pressed and has not. Both now take
the row and fall back to GroupTarget for the desktop's menu, and
ConfirmMoveGroupAsync resolves from the panel's own movingGroupId rather than
from the selection, which is also the honester answer on the desktop: what moves
is the shelf the panel was opened on.

The heading's pencil became a menu. Three icons after a chevron, a name, a vault
badge and a count is what would be left of the name at 360dp, so the ⋯ raises
the add sheet's shape carrying Edit, Move to another vault, a rule, and Delete —
the desktop's card menu, in the one idiom this screen already has. It does not
carry Open: the desktop's grid holds one level of the group tree and this list
holds all of it flattened, so there is nowhere to open a group into.

DELETE under a host sits on a row of its own beneath EDIT and MOVE rather than
beside them. A phone has no hover and no tooltip, so where a thumb lands is the
only thing separating a destructive control from an ordinary one. Both questions
take the controls that asked them — ShowsConnectControls, which is the phone's
half of the rule ShowsHostPaneActions already carries for the desktop's drawer —
so DELETE cannot be pressed a second time underneath its own confirmation.

Preferences gained the running version, and the sentence saying this head does
not replace itself and that no DodoSSH server will ever offer one. It reads
Updates.CurrentVersion off the same view model the desktop's UPDATES section
does, over the null channel that reports itself unsupported.

Nothing was needed for the realtime push: it is composed in ServerConnection,
which both heads use.

Seven tests, all phone-shaped — a group acted on with nothing selected, the menu
waved away leaving nothing armed, the ungrouped heading raising none, and the
bar's three states. The rectangles remain unmeasurable for the reason phase 8
gives; the checks for them are 8.10 to 8.13 and 13.6.

docs/android-port.md

@@ -604,8 +604,20 @@ What is left, in the order it matters:
   the decision above for the shape and for the one thing about it a person will notice — an empty file where
   a failed download was pointed. What is *not* built is a folder picker for several downloads at once: the
   save picker names one destination, so SAVE FILE takes the selected row.
-- **Editors.** There is no host editor and no keychain item editor on the phone, so both are create-on-
-  desktop-and-sync. That is why the v2 design's `+` buttons on HOSTS and on the keychain are not drawn.
+- ~~**Editors.**~~ **Half built.** The v3 hosts screen has both a host editor and a group editor — cards in
+  the list's own row, swapped for the list rather than stacked over it — reached from the design's floating
+  `+` through a sheet asking which of the two is being added. The keychain still has none, so keys,
+  passwords and buckets remain create-on-desktop-and-sync; its one action is DELETE.
+
+  **And everything can now be taken away as well as made.** DELETE under a host, and a group menu on the
+  heading carrying Edit, Move to another vault and Delete — the desktop's card menu, as a bottom sheet,
+  because this head draws no group cards and has no right-click. Both questions replace the controls that
+  asked them rather than stacking over them, which is the rule this document's step 7 already recorded for
+  the keychain's. A screen that could fill a keychain and never empty one was the shape before it.
+
+  The one entry the phone's menu does not carry is Open. The desktop's grid holds one level of the group
+  tree at a time and this list holds all of it flattened, so there is nothing here to open a group *into* —
+  see the correction under *Sidebar* above, which is the same difference stated from the other end.
 - **Pins and import**, which v2 does not draw either. Teams *is* drawn, behind MORE — it was the one of
   the three whose view model needed nothing new on the phone, because none of that screen is vault content.
 - **The App Link upgrade**, unchanged from step 5.