⏪ Revert the LSP notes in testing.md

The protocol cross-link and the TS-internal shutdown-race explanation were
too detailed for the category doc. The helper comment keeps a short,
self-contained note on the stdin-EOF workaround.

development/testing.md

@@ -134,10 +134,7 @@ The script prints the labels the server offers at a `/*COMPLETE*/` marker inside
 is imported by `src/util/__tests__/lsp-completion.test.ts` — which tests the
 helper itself against inline documents, never the library's code — and by
 `src/primitive.test.ts`, where the same probe asserts the matcher's popup;
-the CLI is for manual inspection. It speaks to the server through
-`vscode-languageserver-protocol`'s message connection and typed requests, so the
-transport and protocol plumbing are not hand-rolled (see
-[tooling.md § `vscode-languageserver-protocol` backs the autocomplete helper](./tooling.md#vscode-languageserver-protocol-backs-the-autocomplete-helper)).
+the CLI is for manual inspection.
 
 #### Why
 
@@ -165,13 +162,8 @@ transport and protocol plumbing are not hand-rolled (see
   any order; the file is an integration test (~1.6 s) that needs `node_modules`.
   `didOpen` is handled in order before the completion request, so no settle
   delay is needed.
-- The TS 7 Go server has a shutdown race: `handleExit` returns `io.EOF`, which
-  cancels the background context while `Session.updateWatches` is still running
-  (`internal/project/session.go`), so the bare `context canceled` error is
-  flushed straight to stderr once the outgoing queue is closed, and the server
-  exits 1 even though LSP expects 0 after `shutdown`. The helper therefore sends
-  `shutdown` and then closes stdin instead of sending `exit`; EOF makes the
-  server exit cleanly (code 0, no output), and the kill is kept as a fallback.
+- The server answers some requests with a string id (`client/registerCapability`);
+  the client must tolerate `string | number` ids or the server stalls.
 
 ## Known issues
 

src/util/__tests__/lsp-completion.ts

@@ -145,10 +145,9 @@ export class LspSession {
         return (
             this.#connection
                 .sendRequest(ShutdownRequest.type)
-                // The TS 7 Go server races a background task against the `exit`
-                // notification and logs a bare `context canceled` to stderr as it
-                // tears down (see development/testing.md § Autocomplete). EOF on
-                // stdin shuts it down cleanly instead: exit 0, no output.
+                // The TS 7 Go server logs a bare `context canceled` to stderr
+                // when it handles `exit`; EOF on stdin shuts it down cleanly
+                // (exit 0, no output) instead.
                 .then(() => {
                     this.#child.stdin.end();
                 })