Merge bitcoin#16122: gui: Enable console line edit on setClientModel

2d8ad2f gui: Enable console line edit on setClientModel (João Barbosa)

Pull request description:

  Make console line edit disable by default, and only enable once `RPCConsole::setClientModel` is called.

  Fixes bitcoin#16119.

ACKs for commit 2d8ad2:
  fanquake:
    tACK bitcoin@2d8ad2f on macOS.

Tree-SHA512: 1418ce3c120c08e5ec3e7a7a063572a24402ce0ec541bd4adc21f61d60c4e86b711e82e940ebf5f0445ab861f89c146c2a2e7990fb52bed2c65fc199a1981f71

src/qt/forms/debugwindow.ui

@@ -608,6 +608,9 @@
            <property name="placeholderText">
             <string/>
            </property>
+           <property name="enabled">
+            <bool>false</bool>
+           </property>
           </widget>
          </item>
         </layout>

src/qt/rpcconsole.cpp

@@ -720,6 +720,9 @@ void RPCConsole::setClientModel(ClientModel *model)
         autoCompleter->popup()->setItemDelegate(new QStyledItemDelegate(this));
         autoCompleter->popup()->setObjectName("rpcAutoCompleter");
         autoCompleter->setModelSorting(QCompleter::CaseSensitivelySortedModel);
+        // ui->lineEdit is initially disabled because running commands is only
+        // possible from now on.
+        ui->lineEdit->setEnabled(true);
         ui->lineEdit->setCompleter(autoCompleter);
         autoCompleter->popup()->installEventFilter(this);
         // Start thread to execute RPC commands.