Connections: drop the manual box's view-model state now that both heads ask through the prompt

The phone's Connections screen no longer draws the user@host + password box, and the desktop never
did, so nothing bound VaultViewModel.ManualTarget, ManualPassword, ManualStatus or
ConnectManuallyCommand any more, nor MainWindowViewModel.ConnectToRecentCommand, whose address branch
wrote into that box. They are gone, and so is VaultViewModel.AskAboutHost, whose one caller was
ConnectToRecent. TryParseManualTarget, ManualEndpoint and ConnectToEndpointAsync stay: the prompt, the
desktop's Ctrl+K palette and the phone's hosts search all use them. The reasoning the removed members
carried moved onto ConnectToEndpointAsync and ChoosePromptRecentAsync.

The tests whose subject is still live now go through the prompt instead of the box: a typed address
dialled exactly as typed, port 22 by default, the refusal sentences, the host-key retry replaying the
attempt that raised it, the host-key card staying over the surface it was typed on, the session facts
for a typed password, and no forwards for a typed address. The recent-row cases now drive
ChoosePromptRecentCommand. Two cases existing prompt tests already covered were deleted. Manual check
11.8 now describes recent rows landing on the prompt.

src/DodoSSH.Client.Shell/ViewModels/MainWindowViewModel.cs

@@ -1857,9 +1857,9 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
     /// button needs a command.
     /// </para>
     /// <para>
-    /// Not gated on there being a tab. With nothing open the surface is where a connection is made — the
-    /// phone's terminal screen draws its manual box there, and the desktop its prompt; see
-    /// <see cref="IsConnectPromptShowing"/> — which is worth being able to reach deliberately.
+    /// Not gated on there being a tab. With nothing open the surface is where a connection is made — both
+    /// heads draw the connect prompt there; see <see cref="IsConnectPromptShowing"/> — which is worth being
+    /// able to reach deliberately.
     /// </para>
     /// </remarks>
     [RelayCommand]
@@ -1946,57 +1946,6 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
         OnPropertyChanged(nameof(HasRecentConnections));
     }
 
-    /// <summary>Goes back to a machine that has been connected to before.</summary>
-    /// <remarks>
-    /// <para>
-    /// <b>Two destinations, because a recent row is one of two different things.</b> One that names a
-    /// keychain host goes to that host on the hosts screen, with whatever that head uses to ask about one
-    /// machine raised over it — the desktop's drawer, the phone's action bar — carrying whatever
-    /// authentication the keychain resolves for it. Connecting from here instead would be a third connect
-    /// path that had to answer all of that again.
-    /// </para>
-    /// <para>
-    /// ◆ <b>It raises that rather than merely selecting the row, and on the phone it has to.</b> Nothing on
-    /// that list means "selected" any more — a tap connects and a long press ticks — so arriving with the
-    /// host selected and nothing else would be arriving at a screen with nothing to press. Asking to go back
-    /// to a machine is exactly the deliberate act those flags exist to distinguish from browsing. See
-    /// <c>VaultViewModel.AskAboutHost</c>, which is where the two heads' answers are raised together.
-    /// </para>
-    /// <para>
-    /// One that names no item was typed into the manual box, and the log stored exactly what was dialled —
-    /// <c>user@host:port</c>, which is the grammar that box takes. So it goes back into the box, and what
-    /// is deliberately not restored is the password: it was never stored, which is the whole point of the
-    /// manual path, and a field that filled itself in would be claiming otherwise.
-    /// </para>
-    /// <para>
-    /// A host deleted since it was connected to falls through to the address, which is the honest answer:
-    /// the machine is still there and the keychain no longer knows about it. So does a host in a vault the
-    /// user has switched off, and for the same reason rather than by accident: selecting it would point the
-    /// hosts screen at a row that screen is not drawing, and the grid would null the selection straight back
-    /// out — arriving at the hosts screen with nothing selected and no explanation.
-    /// </para>
-    /// </remarks>
-    [RelayCommand]
-    private void ConnectToRecent(ConnectionLogRowViewModel row)
-    {
-        if (row is null || Vault is not { } vault)
-        {
-            return;
-        }
-
-        if (row.HostId is { } hostId
-            && vault.Hosts.FirstOrDefault(host => host.EntityId == hostId) is { } known
-            && vault.IsVaultShown(known.VaultId))
-        {
-            vault.AskAboutHostCommand.Execute(known);
-            ShowScreen(ShellScreen.Hosts);
-            return;
-        }
-
-        vault.ManualTarget = row.Address;
-        vault.ManualStatus = string.Empty;
-    }
-
     // ---- The rail's own page grouping ----
 
     /// <summary>
@@ -2602,10 +2551,20 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
     /// A click on one of the recent connections printed under the prompt.
     /// </summary>
     /// <remarks>
-    /// A row naming a host still in the keychain goes to that host, with whatever the keychain knows about
-    /// it; one that names none — or a host deleted since — is the address that was dialled, and asks for its
-    /// password the way a typed one does. The same split <see cref="ConnectToRecent"/> makes, and for its
-    /// reason, except that here the answer is a line of the prompt rather than another screen.
+    /// <para>
+    /// <b>Two answers, because a recent row is one of two different things.</b> A row naming a host still in
+    /// the keychain goes to that host, with whatever the keychain knows about it — its key, its saved
+    /// password, its refusals — exactly as typing its name would. One that names none was typed in as an
+    /// address, and the log stored exactly what was dialled, <c>user@host:port</c>, which is the grammar the
+    /// prompt takes. So it goes back onto the prompt and asks for its password the way a typed one does; the
+    /// password was never stored, which is the whole point of that path.
+    /// </para>
+    /// <para>
+    /// A host deleted since it was connected to falls through to the address, which is the honest answer:
+    /// the machine is still there and the keychain no longer knows about it. So does a host in a vault the
+    /// user has switched off, and for the same reason rather than by accident: taking it would reach a host
+    /// the rest of the application is deliberately not showing.
+    /// </para>
     /// </remarks>
     [RelayCommand(AllowConcurrentExecutions = true)]
     private async Task ChoosePromptRecentAsync(ConnectionLogRowViewModel? row)
@@ -2807,13 +2766,13 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
     /// <para>
     /// <b>The palette's answer to a machine that is not in the keychain.</b> Every other row it offers is a
     /// saved host, and a box somebody has just been given the address of had no way in on this head short of
-    /// saving it first — the phone has had a manual box on its terminal screen all along. The query already
-    /// is a box, and <c>user@host</c> is the grammar people type into one, so the palette reads it rather
-    /// than growing a second field.
+    /// saving it first. The query already is a box, and <c>user@host</c> is the grammar people type into
+    /// one, so the palette reads it rather than growing a second field.
     /// </para>
     /// <para>
-    /// Read with <see cref="VaultViewModel.TryParseManualTarget"/>, which is the phone's box's own parser, so
-    /// the two heads accept exactly the same addresses and refuse the rest with the same sentences.
+    /// Read with <see cref="VaultViewModel.TryParseManualTarget"/>, which is the connect prompt's parser and
+    /// the phone's hosts search's too, so every box accepts exactly the same addresses and refuses the rest
+    /// with the same sentences.
     /// </para>
     /// <para>
     /// Only a query with an <c>@</c> in it is read at all. Without one, everything typed is a search, and a
@@ -2884,7 +2843,7 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
 
     /// <summary>The password typed for <see cref="AdHocTarget"/>.</summary>
     /// <remarks>
-    /// Cleared whenever the palette closes or goes back to the query, on the same terms the phone's manual box
+    /// Cleared whenever the palette closes or goes back to the query, on the same terms the connect prompt
     /// clears its own: it is a secret nobody asked to keep, and the next address typed must not arrive with the
     /// last one's password already in the box.
     /// </remarks>
@@ -3001,8 +2960,8 @@ internal sealed partial class MainWindowViewModel : ObservableObject, IAsyncDisp
     /// </summary>
     /// <remarks>
     /// <para>
-    /// Through <see cref="VaultViewModel.ConnectToEndpointAsync"/>, which is the phone's manual box's own
-    /// path, so a machine reached from here gets the same tab, the same host-key question and the same
+    /// Through <see cref="VaultViewModel.ConnectToEndpointAsync"/>, which is the connect prompt's own path,
+    /// so a machine reached from here gets the same tab, the same host-key question and the same
     /// connection-log entry. What is written, if the user answers the host-key question, is a pin — the trust
     /// decision belongs to the endpoint rather than to a keychain item, and a machine reached this way is
     /// exactly the one whose key nobody has seen before.