Adjust design of the slash command picker (#19973)

This PR removes the quote selection icon button from the footer and adds
it in the picker, and adds an icon field to each command entry. Final
result looks like:


https://github.com/user-attachments/assets/d177f1c1-b6f6-4652-9434-f6291b279e34

Release Notes:

- N/A

crates/assistant/src/slash_command/auto_command.rs

@@ -14,7 +14,7 @@ use language_model::{
 use semantic_index::{FileSummary, SemanticDb};
 use smol::channel;
 use std::sync::{atomic::AtomicBool, Arc};
-use ui::{BorrowAppContext, WindowContext};
+use ui::{prelude::*, BorrowAppContext, WindowContext};
 use util::ResultExt;
 use workspace::Workspace;
 
@@ -37,6 +37,10 @@ impl SlashCommand for AutoCommand {
         "Automatically infer what context to add".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::Wand
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/delta_command.rs

@@ -10,6 +10,7 @@ use gpui::{Task, WeakView, WindowContext};
 use language::{BufferSnapshot, LspAdapterDelegate};
 use std::sync::{atomic::AtomicBool, Arc};
 use text::OffsetRangeExt;
+use ui::prelude::*;
 use workspace::Workspace;
 
 pub(crate) struct DeltaSlashCommand;
@@ -27,6 +28,10 @@ impl SlashCommand for DeltaSlashCommand {
         self.description()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::Diff
+    }
+
     fn requires_argument(&self) -> bool {
         false
     }

crates/assistant/src/slash_command/diagnostics_command.rs

@@ -98,6 +98,10 @@ impl SlashCommand for DiagnosticsSlashCommand {
         "Insert diagnostics".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::XCircle
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/file_command.rs

@@ -117,7 +117,7 @@ impl SlashCommand for FileSlashCommand {
     }
 
     fn description(&self) -> String {
-        "Insert file".into()
+        "Insert file and/or directory".into()
     }
 
     fn menu_text(&self) -> String {
@@ -128,6 +128,10 @@ impl SlashCommand for FileSlashCommand {
         true
     }
 
+    fn icon(&self) -> IconName {
+        IconName::File
+    }
+
     fn complete_argument(
         self: Arc<Self>,
         arguments: &[String],

crates/assistant/src/slash_command/project_command.rs

@@ -24,7 +24,8 @@ use std::{
     ops::DerefMut,
     sync::{atomic::AtomicBool, Arc},
 };
-use ui::{BorrowAppContext as _, IconName};
+
+use ui::prelude::*;
 use workspace::Workspace;
 
 pub struct ProjectSlashCommand {
@@ -50,6 +51,10 @@ impl SlashCommand for ProjectSlashCommand {
         "Generate a semantic search based on context".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::Folder
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/prompt_command.rs

@@ -21,6 +21,10 @@ impl SlashCommand for PromptSlashCommand {
         "Insert prompt from library".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::Library
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/search_command.rs

@@ -38,6 +38,10 @@ impl SlashCommand for SearchSlashCommand {
         "Search your project semantically".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::SearchCode
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/symbols_command.rs

@@ -22,6 +22,10 @@ impl SlashCommand for OutlineSlashCommand {
         "Insert symbols for active tab".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::ListTree
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/tab_command.rs

@@ -12,7 +12,7 @@ use std::{
     path::PathBuf,
     sync::{atomic::AtomicBool, Arc},
 };
-use ui::{ActiveTheme, WindowContext};
+use ui::{prelude::*, ActiveTheme, WindowContext};
 use util::ResultExt;
 use workspace::Workspace;
 
@@ -31,6 +31,10 @@ impl SlashCommand for TabSlashCommand {
         "Insert open tabs (active tab by default)".to_owned()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::FileTree
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }

crates/assistant/src/slash_command/terminal_command.rs

@@ -33,6 +33,10 @@ impl SlashCommand for TerminalSlashCommand {
         "Insert terminal output".into()
     }
 
+    fn icon(&self) -> IconName {
+        IconName::Terminal
+    }
+
     fn menu_text(&self) -> String {
         self.description()
     }