Overhaul extension registration (#21083)

This PR overhauls extension registration in order to make it more
modular.

The `extension` crate now contains an `ExtensionHostProxy` that can be
used to register various proxies that the extension host can use to
interact with the rest of the system.

There are now a number of different proxy traits representing the
various pieces of functionality that can be provided by an extension.
The respective crates that provide this functionality can implement
their corresponding proxy trait in order to register a proxy that the
extension host will use to register the bits of functionality provided
by the extension.

Release Notes:

- N/A

crates/extension_host/src/wasm_host/wit/since_v0_0_1.rs

@@ -3,7 +3,7 @@ use crate::wasm_host::wit::since_v0_0_4;
 use crate::wasm_host::WasmState;
 use anyhow::Result;
 use async_trait::async_trait;
-use extension::WorktreeDelegate;
+use extension::{ExtensionLanguageServerProxy, WorktreeDelegate};
 use language::LanguageServerBinaryStatus;
 use semantic_version::SemanticVersion;
 use std::sync::{Arc, OnceLock};
@@ -149,8 +149,9 @@ impl ExtensionImports for WasmState {
         };
 
         self.host
-            .registration_hooks
-            .update_lsp_status(lsp::LanguageServerName(server_name.into()), status);
+            .proxy
+            .update_language_server_status(lsp::LanguageServerName(server_name.into()), status);
+
         Ok(())
     }
 

crates/extension_host/src/wasm_host/wit/since_v0_1_0.rs

@@ -5,7 +5,7 @@ use anyhow::{anyhow, bail, Context, Result};
 use async_compression::futures::bufread::GzipDecoder;
 use async_tar::Archive;
 use async_trait::async_trait;
-use extension::{KeyValueStoreDelegate, WorktreeDelegate};
+use extension::{ExtensionLanguageServerProxy, KeyValueStoreDelegate, WorktreeDelegate};
 use futures::{io::BufReader, FutureExt as _};
 use futures::{lock::Mutex, AsyncReadExt};
 use language::LanguageName;
@@ -495,8 +495,9 @@ impl ExtensionImports for WasmState {
         };
 
         self.host
-            .registration_hooks
-            .update_lsp_status(::lsp::LanguageServerName(server_name.into()), status);
+            .proxy
+            .update_language_server_status(::lsp::LanguageServerName(server_name.into()), status);
+
         Ok(())
     }
 

crates/extension_host/src/wasm_host/wit/since_v0_2_0.rs

@@ -8,7 +8,9 @@ use async_compression::futures::bufread::GzipDecoder;
 use async_tar::Archive;
 use async_trait::async_trait;
 use context_servers::manager::ContextServerSettings;
-use extension::{KeyValueStoreDelegate, ProjectDelegate, WorktreeDelegate};
+use extension::{
+    ExtensionLanguageServerProxy, KeyValueStoreDelegate, ProjectDelegate, WorktreeDelegate,
+};
 use futures::{io::BufReader, FutureExt as _};
 use futures::{lock::Mutex, AsyncReadExt};
 use language::{language_settings::AllLanguageSettings, LanguageName, LanguageServerBinaryStatus};
@@ -682,8 +684,9 @@ impl ExtensionImports for WasmState {
         };
 
         self.host
-            .registration_hooks
-            .update_lsp_status(::lsp::LanguageServerName(server_name.into()), status);
+            .proxy
+            .update_language_server_status(::lsp::LanguageServerName(server_name.into()), status);
+
         Ok(())
     }