Enable TS Server plugins on web (#47377)

* Prototype TS plugins on web

This prototype allows service plugins to be loaded on web TSServer

Main changes:

- Adds a new host entryPoint called `importServicePlugin` for overriding how plugins can be loaded. This may be async
- Implement `importServicePlugin` for webServer
- The web server plugin implementation looks for a `browser` field in the plugin's `package.json`
- It then uses `import(...)` to load the plugin (the plugin source must be compiled to support being loaded as a module)

* use default export from plugins

This more or less matches how node plugins expect the plugin module to be an init function

* Allow configure plugin requests against any web servers in partial semantic mode

* Addressing some comments

- Use result value instead of try/catch (`ImportPluginResult`)
- Add awaits
- Add logging

* add tsserverWeb to patch in dynamic import

* Remove eval

We should throw instead when dynamic import is not implemented

* Ensure dynamically imported plugins are loaded in the correct order

* Add tests for async service plugin timing

* Update src/server/editorServices.ts

Co-authored-by: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>

* Partial PR feedback

* Rename tsserverWeb to dynamicImportCompat

* Additional PR feedback

Co-authored-by: Ron Buckton <ron.buckton@microsoft.com>
Co-authored-by: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>

scripts/produceLKG.ts

@@ -62,6 +62,7 @@ async function copyScriptOutputs() {
     await copyWithCopyright("cancellationToken.js");
     await copyWithCopyright("tsc.release.js", "tsc.js");
     await copyWithCopyright("tsserver.js");
+    await copyWithCopyright("dynamicImportCompat.js");
     await copyFromBuiltLocal("tsserverlibrary.js"); // copyright added by build
     await copyFromBuiltLocal("typescript.js"); // copyright added by build
     await copyFromBuiltLocal("typescriptServices.js"); // copyright added by build