Implement rendering of images with data urls in markdown (#30322)

Fixes #28266

![Screenshot 2025-05-08 at 5 08
21 PM](https://github.com/user-attachments/assets/774d2dde-3f2d-466c-8eb1-c67badbd89e4)

Release Notes:

- Added support for rendering images with data URLs in markdown. This
can show up in hover documentation provided by language servers.

Co-authored-by: Mikayla Maki <mikayla.c.maki@gmail.com>

crates/gpui/src/platform.rs

@@ -36,7 +36,7 @@ use crate::{
     ForegroundExecutor, GlyphId, GpuSpecs, ImageSource, Keymap, LineLayout, Pixels, PlatformInput,
     Point, RenderGlyphParams, RenderImage, RenderImageParams, RenderSvgParams, ScaledPixels, Scene,
     ShapedGlyph, ShapedRun, SharedString, Size, SvgRenderer, SvgSize, Task, TaskLabel, Window,
-    point, px, size,
+    hash, point, px, size,
 };
 use anyhow::Result;
 use async_task::Runnable;
@@ -1499,6 +1499,20 @@ impl ImageFormat {
             ImageFormat::Tiff => "image/tiff",
         }
     }
+
+    /// Returns the ImageFormat for the given mime type
+    pub fn from_mime_type(mime_type: &str) -> Option<Self> {
+        match mime_type {
+            "image/png" => Some(Self::Png),
+            "image/jpeg" | "image/jpg" => Some(Self::Jpeg),
+            "image/webp" => Some(Self::Webp),
+            "image/gif" => Some(Self::Gif),
+            "image/svg+xml" => Some(Self::Svg),
+            "image/bmp" => Some(Self::Bmp),
+            "image/tiff" | "image/tif" => Some(Self::Tiff),
+            _ => None,
+        }
+    }
 }
 
 /// An image, with a format and certain bytes
@@ -1509,7 +1523,7 @@ pub struct Image {
     /// The raw image bytes
     pub bytes: Vec<u8>,
     /// The unique ID for the image
-    pub id: u64,
+    id: u64,
 }
 
 impl Hash for Image {
@@ -1521,10 +1535,15 @@ impl Hash for Image {
 impl Image {
     /// An empty image containing no data
     pub fn empty() -> Self {
+        Self::from_bytes(ImageFormat::Png, Vec::new())
+    }
+
+    /// Create an image from a format and bytes
+    pub fn from_bytes(format: ImageFormat, bytes: Vec<u8>) -> Self {
         Self {
-            format: ImageFormat::Png,
-            bytes: Vec::new(),
-            id: 0,
+            id: hash(&bytes),
+            format,
+            bytes,
         }
     }
 

crates/gpui/src/window.rs

@@ -2100,14 +2100,14 @@ impl Window {
         let (task, is_first) = cx.fetch_asset::<A>(source);
         task.clone().now_or_never().or_else(|| {
             if is_first {
-                let entity = self.current_view();
+                let entity_id = self.current_view();
                 self.spawn(cx, {
                     let task = task.clone();
                     async move |cx| {
                         task.await;
 
                         cx.on_next_frame(move |_, cx| {
-                            cx.notify(entity);
+                            cx.notify(entity_id);
                         });
                     }
                 })