ui: Track changes to UI font size made via actions with settings (#23265)

Fixes #5380

Closes #5380

Release Notes:

- Font size changes made with actions are now persisted in user settings

crates/repl/src/outputs/plain.rs

@@ -60,6 +60,7 @@ const DEFAULT_NUM_COLUMNS: usize = 128;
 pub fn text_style(cx: &mut WindowContext) -> TextStyle {
     let settings = ThemeSettings::get_global(cx).clone();
 
+    let font_size = settings.buffer_font_size().into();
     let font_family = settings.buffer_font.family;
     let font_features = settings.buffer_font.features;
     let font_weight = settings.buffer_font.weight;
@@ -72,7 +73,7 @@ pub fn text_style(cx: &mut WindowContext) -> TextStyle {
         font_features,
         font_weight,
         font_fallbacks,
-        font_size: theme::get_buffer_font_size(cx).into(),
+        font_size,
         font_style: FontStyle::Normal,
         line_height: cx.line_height().into(),
         background_color: Some(theme.colors().terminal_ansi_background),