Add spawning of tasks without saving them in the task stack (#9951)

These tasks are not considered for reruns with `task::Rerun`. 
This PR tears a bunch of stuff up around tasks:
- `menu::SecondaryConfirm` for tasks is gonna spawn a task without
storing it in history instead of being occupied by oneshot tasks. This
is done so that cmd-clicking on the menu item actually does something
meaningful.
- `menu::UseSelectedQuery` got moved into picker, as tasks are it's only
user (and it doesn't really make sense as a menu action).

TODO:
- [x] add release note
- [x] Actually implement the core of this feature, which is spawning a
task without saving it in history, lol.

Fixes #9804 
Release Notes:

- Added "fire-and-forget" task spawning; `menu::SecondaryConfirm` in
tasks modal now spawns a task without registering it as the last spawned
task for the purposes of `task::Rerun`. By default you can spawn a task
in this fashion with cmd+enter or by holding cmd and clicking on a task
entry in a list. Spawning oneshots has been rebound to `option-enter`
(under a `picker::ConfirmInput` name). Fixes #9804 (breaking change)
- Moved `menu::UseSelectedQuery` action to `picker` namespace (breaking
change).

crates/picker/Cargo.toml

@@ -17,6 +17,7 @@ anyhow.workspace = true
 editor.workspace = true
 gpui.workspace = true
 menu.workspace = true
+serde.workspace = true
 ui.workspace = true
 workspace.workspace = true
 

crates/picker/src/picker.rs

@@ -1,11 +1,12 @@
 use anyhow::Result;
 use editor::{scroll::Autoscroll, Editor};
 use gpui::{
-    div, list, prelude::*, uniform_list, AnyElement, AppContext, ClickEvent, DismissEvent,
-    EventEmitter, FocusHandle, FocusableView, Length, ListState, MouseButton, MouseUpEvent, Render,
-    Task, UniformListScrollHandle, View, ViewContext, WindowContext,
+    actions, div, impl_actions, list, prelude::*, uniform_list, AnyElement, AppContext, ClickEvent,
+    DismissEvent, EventEmitter, FocusHandle, FocusableView, Length, ListState, MouseButton,
+    MouseUpEvent, Render, Task, UniformListScrollHandle, View, ViewContext, WindowContext,
 };
 use head::Head;
+use serde::Deserialize;
 use std::{sync::Arc, time::Duration};
 use ui::{prelude::*, v_flex, Color, Divider, Label, ListItem, ListItemSpacing};
 use workspace::ModalView;
@@ -18,6 +19,17 @@ enum ElementContainer {
     UniformList(UniformListScrollHandle),
 }
 
+actions!(picker, [UseSelectedQuery]);
+
+/// ConfirmInput is an alternative editor action which - instead of selecting active picker entry - treats pickers editor input literally,
+/// performing some kind of action on it.
+#[derive(PartialEq, Clone, Deserialize, Default)]
+pub struct ConfirmInput {
+    pub secondary: bool,
+}
+
+impl_actions!(picker, [ConfirmInput]);
+
 struct PendingUpdateMatches {
     delegate_update_matches: Option<Task<()>>,
     _task: Task<Result<()>>,
@@ -65,6 +77,9 @@ pub trait PickerDelegate: Sized + 'static {
     }
 
     fn confirm(&mut self, secondary: bool, cx: &mut ViewContext<Picker<Self>>);
+    /// Instead of interacting with currently selected entry, treats editor input literally,
+    /// performing some kind of action on it.
+    fn confirm_input(&mut self, _secondary: bool, _: &mut ViewContext<Picker<Self>>) {}
     fn dismissed(&mut self, cx: &mut ViewContext<Picker<Self>>);
     fn selected_as_query(&self) -> Option<String> {
         None
@@ -278,7 +293,11 @@ impl<D: PickerDelegate> Picker<D> {
         }
     }
 
-    fn use_selected_query(&mut self, _: &menu::UseSelectedQuery, cx: &mut ViewContext<Self>) {
+    fn confirm_input(&mut self, input: &ConfirmInput, cx: &mut ViewContext<Self>) {
+        self.delegate.confirm_input(input.secondary, cx);
+    }
+
+    fn use_selected_query(&mut self, _: &UseSelectedQuery, cx: &mut ViewContext<Self>) {
         if let Some(new_query) = self.delegate.selected_as_query() {
             self.set_query(new_query, cx);
             cx.stop_propagation();
@@ -472,6 +491,7 @@ impl<D: PickerDelegate> Render for Picker<D> {
             .on_action(cx.listener(Self::confirm))
             .on_action(cx.listener(Self::secondary_confirm))
             .on_action(cx.listener(Self::use_selected_query))
+            .on_action(cx.listener(Self::confirm_input))
             .child(match &self.head {
                 Head::Editor(editor) => v_flex()
                     .child(