Copy/paste images into editors (Mac only) (#15782)

For future reference: WIP branch of copy/pasting a mixture of images and
text: https://github.com/zed-industries/zed/tree/copy-paste-images -
we'll come back to that one after landing this one.

Release Notes:

- You can now paste images into the Assistant Panel to include them as
context. Currently works only on Mac, and with Anthropic models. Future
support is planned for more models, operating systems, and image
clipboard operations.

---------

Co-authored-by: Antonio <antonio@zed.dev>
Co-authored-by: Mikayla <mikayla@zed.dev>
Co-authored-by: Jason <jason@zed.dev>
Co-authored-by: Kyle <kylek@zed.dev>

crates/gpui/src/asset_cache.rs

@@ -1,17 +1,14 @@
-use crate::{SharedString, SharedUri, WindowContext};
-use collections::FxHashMap;
+use crate::{AppContext, SharedString, SharedUri};
 use futures::Future;
-use parking_lot::Mutex;
-use std::any::TypeId;
 use std::hash::{Hash, Hasher};
+use std::path::PathBuf;
 use std::sync::Arc;
-use std::{any::Any, path::PathBuf};
 
 #[derive(Debug, PartialEq, Eq, Hash, Clone)]
 pub(crate) enum UriOrPath {
     Uri(SharedUri),
     Path(Arc<PathBuf>),
-    Asset(SharedString),
+    Embedded(SharedString),
 }
 
 impl From<SharedUri> for UriOrPath {
@@ -37,7 +34,7 @@ pub trait Asset {
     /// Load the asset asynchronously
     fn load(
         source: Self::Source,
-        cx: &mut WindowContext,
+        cx: &mut AppContext,
     ) -> impl Future<Output = Self::Output> + Send + 'static;
 }
 
@@ -47,42 +44,3 @@ pub fn hash<T: Hash>(data: &T) -> u64 {
     data.hash(&mut hasher);
     hasher.finish()
 }
-
-/// A cache for assets.
-#[derive(Clone)]
-pub struct AssetCache {
-    assets: Arc<Mutex<FxHashMap<(TypeId, u64), Box<dyn Any + Send>>>>,
-}
-
-impl AssetCache {
-    pub(crate) fn new() -> Self {
-        Self {
-            assets: Default::default(),
-        }
-    }
-
-    /// Get the asset from the cache, if it exists.
-    pub fn get<A: Asset + 'static>(&self, source: &A::Source) -> Option<A::Output> {
-        self.assets
-            .lock()
-            .get(&(TypeId::of::<A>(), hash(&source)))
-            .and_then(|task| task.downcast_ref::<A::Output>())
-            .cloned()
-    }
-
-    /// Insert the asset into the cache.
-    pub fn insert<A: Asset + 'static>(&mut self, source: A::Source, output: A::Output) {
-        self.assets
-            .lock()
-            .insert((TypeId::of::<A>(), hash(&source)), Box::new(output));
-    }
-
-    /// Remove an entry from the asset cache
-    pub fn remove<A: Asset + 'static>(&mut self, source: &A::Source) -> Option<A::Output> {
-        self.assets
-            .lock()
-            .remove(&(TypeId::of::<A>(), hash(&source)))
-            .and_then(|any| any.downcast::<A::Output>().ok())
-            .map(|boxed| *boxed)
-    }
-}