Inline git blame (#10398)

This adds so-called "inline git blame" to the editor that, when turned
on, shows `git blame` information about the current line inline:


![screenshot-2024-04-15-11 29
35@2x](https://github.com/zed-industries/zed/assets/1185253/21cef7be-3283-4556-a9f0-cc349c4e1d75)


When the inline information is hovered, a new tooltip appears that
contains more information on the current commit:


![screenshot-2024-04-15-11 28
24@2x](https://github.com/zed-industries/zed/assets/1185253/ee128460-f6a2-48c2-a70d-e03ff90a737f)

The commit message in this tooltip is rendered as Markdown, is
scrollable and clickable.

The tooltip is now also the tooltip used in the gutter:

![screenshot-2024-04-15-11 28
51@2x](https://github.com/zed-industries/zed/assets/1185253/42be3d63-91d0-4936-8183-570e024beabe)


## Settings

1. The inline git blame information can be turned on and off via
settings:
```json
{
  "git": {
    "inline_blame": {
      "enabled": true
    }
  }
}
```
2. Optionally, a delay can be configured. When a delay is set, the
inline blame information will only show up `x milliseconds` after a
cursor movement:
```json
{
  "git": {
    "inline_blame": {
      "enabled": true,
      "delay_ms": 600
    }
  }
}
```
3. It can also be turned on/off for the current buffer with `editor:
toggle git blame inline`.

## To be done in follow-up PRs

- [ ] Add link to pull request in tooltip
- [ ] Add avatars of users if possible

## Release notes

Release Notes:

- Added inline `git blame` information the editor. It can be turned on
in the settings with `{"git": { "inline_blame": "on" } }` for every
buffer or, temporarily for the current buffer, with `editor: toggle git
blame inline`.

crates/time_format/src/time_format.rs

@@ -9,6 +9,8 @@ pub enum TimestampFormat {
     /// If the message is from today or yesterday the date will be replaced with "Today at x" or "Yesterday at x" respectively.
     /// E.g. "Today at 12:00 PM", "Yesterday at 11:00 AM", "2021-12-31 3:00AM".
     EnhancedAbsolute,
+    /// Formats the timestamp as an absolute time, using month name, day of month, year. e.g. "Feb. 24, 2024".
+    MediumAbsolute,
     /// Formats the timestamp as a relative time, e.g. "just now", "1 minute ago", "2 hours ago", "2 months ago".
     Relative,
 }
@@ -30,6 +32,9 @@ pub fn format_localized_timestamp(
         TimestampFormat::EnhancedAbsolute => {
             format_absolute_timestamp(timestamp_local, reference_local, true)
         }
+        TimestampFormat::MediumAbsolute => {
+            format_absolute_timestamp_medium(timestamp_local, reference_local)
+        }
         TimestampFormat::Relative => format_relative_time(timestamp_local, reference_local)
             .unwrap_or_else(|| format_relative_date(timestamp_local, reference_local)),
     }
@@ -72,6 +77,22 @@ fn format_absolute_timestamp(
     }
 }
 
+fn format_absolute_timestamp_medium(
+    timestamp: OffsetDateTime,
+    #[allow(unused_variables)] reference: OffsetDateTime,
+) -> String {
+    #[cfg(target_os = "macos")]
+    {
+        macos::format_date_medium(&timestamp)
+    }
+    #[cfg(not(target_os = "macos"))]
+    {
+        // todo(linux) respect user's date/time preferences
+        // todo(windows) respect user's date/time preferences
+        format_timestamp_fallback(timestamp, reference)
+    }
+}
+
 fn format_relative_time(timestamp: OffsetDateTime, reference: OffsetDateTime) -> Option<String> {
     let difference = reference - timestamp;
     let minutes = difference.whole_minutes();
@@ -253,7 +274,8 @@ mod macos {
     use core_foundation_sys::{
         base::kCFAllocatorDefault,
         date_formatter::{
-            kCFDateFormatterNoStyle, kCFDateFormatterShortStyle, CFDateFormatterCreate,
+            kCFDateFormatterMediumStyle, kCFDateFormatterNoStyle, kCFDateFormatterShortStyle,
+            CFDateFormatterCreate,
         },
         locale::CFLocaleCopyCurrent,
     };
@@ -266,6 +288,10 @@ mod macos {
         format_with_date_formatter(timestamp, DATE_FORMATTER.with(|f| *f))
     }
 
+    pub fn format_date_medium(timestamp: &time::OffsetDateTime) -> String {
+        format_with_date_formatter(timestamp, MEDIUM_DATE_FORMATTER.with(|f| *f))
+    }
+
     fn format_with_date_formatter(
         timestamp: &time::OffsetDateTime,
         fmt: CFDateFormatterRef,
@@ -302,6 +328,15 @@ mod macos {
                 kCFDateFormatterNoStyle,
             )
         };
+
+        static MEDIUM_DATE_FORMATTER: CFDateFormatterRef = unsafe {
+            CFDateFormatterCreate(
+                kCFAllocatorDefault,
+                CURRENT_LOCALE.with(|locale| *locale),
+                kCFDateFormatterMediumStyle,
+                kCFDateFormatterNoStyle,
+            )
+        };
     }
 }