Switch LSP prompts to use a non-blocking toast (#8312)

This fixes a major degradation in usability that some users ran into.

Fixes https://github.com/zed-industries/zed/issues/8255 
Fixes https://github.com/zed-industries/zed/issues/8229

Release Notes:

- Switch from using platform prompts to toasts for LSP prompts.
([8255](https://github.com/zed-industries/zed/issues/8255),
[8229](https://github.com/zed-industries/zed/issues/8229))

<img width="583" alt="Screenshot 2024-02-23 at 2 40 05 PM"
src="https://github.com/zed-industries/zed/assets/2280405/1bfc027b-b7a8-4563-88b6-020e47869668">

Co-authored-by: Marshall <marshall@zed.dev>

crates/ui/src/components/label/label_like.rs

@@ -7,6 +7,7 @@ use crate::prelude::*;
 pub enum LabelSize {
     #[default]
     Default,
+    Large,
     Small,
     XSmall,
 }
@@ -97,6 +98,7 @@ impl RenderOnce for LabelLike {
                 )
             })
             .map(|this| match self.size {
+                LabelSize::Large => this.text_ui_lg(),
                 LabelSize::Default => this.text_ui(),
                 LabelSize::Small => this.text_ui_sm(),
                 LabelSize::XSmall => this.text_ui_xs(),

crates/ui/src/styled_ext.rs

@@ -35,6 +35,17 @@ pub trait StyledExt: Styled + Sized {
         self.text_size(size.rems())
     }
 
+    /// The large size for UI text.
+    ///
+    /// `1rem` or `16px` at the default scale of `1rem` = `16px`.
+    ///
+    /// Note: The absolute size of this text will change based on a user's `ui_scale` setting.
+    ///
+    /// Use `text_ui` for regular-sized text.
+    fn text_ui_lg(self) -> Self {
+        self.text_size(UiTextSize::Large.rems())
+    }
+
     /// The default size for UI text.
     ///
     /// `0.825rem` or `14px` at the default scale of `1rem` = `16px`.

crates/ui/src/styles/typography.rs

@@ -13,6 +13,13 @@ pub enum UiTextSize {
     /// Note: The absolute size of this text will change based on a user's `ui_scale` setting.
     #[default]
     Default,
+    /// The large size for UI text.
+    ///
+    /// `1rem` or `16px` at the default scale of `1rem` = `16px`.
+    ///
+    /// Note: The absolute size of this text will change based on a user's `ui_scale` setting.
+    Large,
+
     /// The small size for UI text.
     ///
     /// `0.75rem` or `12px` at the default scale of `1rem` = `16px`.
@@ -31,6 +38,7 @@ pub enum UiTextSize {
 impl UiTextSize {
     pub fn rems(self) -> Rems {
         match self {
+            Self::Large => rems(16. / 16.),
             Self::Default => rems(14. / 16.),
             Self::Small => rems(12. / 16.),
             Self::XSmall => rems(10. / 16.),