settings_ui: Expose background image settings on the Appearance page

Adds Image Path, Fit and Opacity controls to the Appearance settings page
so the workspace background image can be configured in-app instead of
editing settings JSON.

crates/settings_content/src/background_image.rs

@@ -4,9 +4,9 @@ use settings_macros::MergeFrom;
 
 /// Determines how the workspace background image is fitted into the window bounds.
 ///
-/// Default: cover
 #[derive(
     Copy, Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize, JsonSchema, MergeFrom,
+    strum::VariantArray, strum::VariantNames,
 )]
 #[serde(rename_all = "snake_case")]
 pub enum BackgroundImageFit {

crates/settings_ui/src/page_data.rs

@@ -1530,6 +1530,69 @@ fn appearance_page() -> SettingsPage {
         ]
     }
 
+    fn background_image_section() -> [SettingsPageItem; 4] {
+        [
+            SettingsPageItem::SectionHeader("Background Image"),
+            SettingsPageItem::SettingItem(SettingItem {
+                title: "Image Path",
+                description: "Path to the image displayed behind the workspace UI. `~` and environment variables are expanded. Leave empty to disable.",
+                field: Box::new(SettingField {
+                    organization_override: None,
+                    json_path: Some("background.path"),
+                    pick: |settings_content| {
+                        settings_content.background.as_ref()?.path.as_ref()
+                    },
+                    write: |settings_content, value, _| {
+                        settings_content
+                            .background
+                            .get_or_insert_default()
+                            .path = value;
+                    },
+                }),
+                metadata: None,
+                files: USER,
+            }),
+            SettingsPageItem::SettingItem(SettingItem {
+                title: "Fit",
+                description: "How the image is fitted into the workspace bounds.",
+                field: Box::new(SettingField {
+                    organization_override: None,
+                    json_path: Some("background.fit"),
+                    pick: |settings_content| {
+                        settings_content.background.as_ref()?.fit.as_ref()
+                    },
+                    write: |settings_content, value, _| {
+                        settings_content
+                            .background
+                            .get_or_insert_default()
+                            .fit = value;
+                    },
+                }),
+                metadata: None,
+                files: USER,
+            }),
+            SettingsPageItem::SettingItem(SettingItem {
+                title: "Opacity",
+                description: "Opacity of the background image, between 0.0 (fully transparent) and 1.0 (fully opaque).",
+                field: Box::new(SettingField {
+                    organization_override: None,
+                    json_path: Some("background.opacity"),
+                    pick: |settings_content| {
+                        settings_content.background.as_ref()?.opacity.as_ref()
+                    },
+                    write: |settings_content, value, _| {
+                        settings_content
+                            .background
+                            .get_or_insert_default()
+                            .opacity = value;
+                    },
+                }),
+                metadata: None,
+                files: USER,
+            }),
+        ]
+    }
+
     let items: Box<[SettingsPageItem]> = concat_sections!(
         theme_section(),
         buffer_font_section(),
@@ -1540,6 +1603,7 @@ fn appearance_page() -> SettingsPage {
         cursor_section(),
         highlighting_section(),
         guides_section(),
+        background_image_section(),
     );
 
     SettingsPage {

crates/settings_ui/src/settings_ui.rs

@@ -674,6 +674,7 @@ fn init_renderers(cx: &mut App) {
         .add_basic_renderer::<settings::AudioInputDeviceName>(render_input_audio_device_dropdown)
         .add_basic_renderer::<settings::AudioOutputDeviceName>(render_output_audio_device_dropdown)
         .add_basic_renderer::<settings::TerminalBell>(render_dropdown)
+        .add_basic_renderer::<settings::BackgroundImageFit>(render_dropdown)
         // please semicolon stay on next line
         ;
 }