add a setting to control show/hide terminal button for status bar (#10593)

Release Notes:

- Added a setting to show/hide the terminal button in the status bar:
`{"terminal": {"button": false}}` to hide it. (#10513)

---------

Co-authored-by: Thorsten Ball <mrnugget@gmail.com>

crates/terminal_view/src/terminal_panel.rs

@@ -726,8 +726,10 @@ impl Panel for TerminalPanel {
         "TerminalPanel"
     }
 
-    fn icon(&self, _cx: &WindowContext) -> Option<IconName> {
-        Some(IconName::Terminal)
+    fn icon(&self, cx: &WindowContext) -> Option<IconName> {
+        TerminalSettings::get_global(cx)
+            .button
+            .then(|| IconName::Terminal)
     }
 
     fn icon_tooltip(&self, _cx: &WindowContext) -> Option<&'static str> {