Fix missed renames in #22632 (#23688)

Fix a bug where a GPUI macro still used `ModelContext`
Rename `AsyncAppContext` -> `AsyncApp`
Rename update_model, read_model, insert_model, and reserve_model to
update_entity, read_entity, insert_entity, and reserve_entity

Release Notes:

- N/A

crates/languages/src/go.rs

@@ -2,7 +2,7 @@ use anyhow::{anyhow, Context as _, Result};
 use async_trait::async_trait;
 use collections::HashMap;
 use futures::StreamExt;
-use gpui::{App, AsyncAppContext, Task};
+use gpui::{App, AsyncApp, Task};
 use http_client::github::latest_github_release;
 pub use language::*;
 use lsp::{LanguageServerBinary, LanguageServerName};
@@ -76,7 +76,7 @@ impl super::LspAdapter for GoLspAdapter {
         &self,
         delegate: &dyn LspAdapterDelegate,
         _: Arc<dyn LanguageToolchainStore>,
-        _: &AsyncAppContext,
+        _: &AsyncApp,
     ) -> Option<LanguageServerBinary> {
         let path = delegate.which(Self::SERVER_NAME.as_ref()).await?;
         Some(LanguageServerBinary {
@@ -89,7 +89,7 @@ impl super::LspAdapter for GoLspAdapter {
     fn will_fetch_server(
         &self,
         delegate: &Arc<dyn LspAdapterDelegate>,
-        cx: &mut AsyncAppContext,
+        cx: &mut AsyncApp,
     ) -> Option<Task<Result<()>>> {
         static DID_SHOW_NOTIFICATION: AtomicBool = AtomicBool::new(false);