📝 Drop the stale scripts test glob from testing.md

No tests live under scripts/, and every test script (test, test:unit, test:ci,
watch:test) globs only src/**/*.test.ts, so state that. The scripts/**
oxlint scope it was confused with still exists and carries the same
import/no-nodejs-modules exception as the test-helper scope.

development/testing.md

@@ -30,8 +30,8 @@ before the implementation.
 - Testing the type only: it would not catch handler dispatch or the `_`
   fallback (see `src/primitive.test.ts`).
 
-The runner is `node --test --strip-types` over `src/**/*.test.ts` and
+The runner is `node --test --strip-types "src/**/*.test.ts"` and the tiers are
-`scripts/**/*.test.ts`; the tiers are in
+in
 [CONTRIBUTING.md § Development commands](../CONTRIBUTING.md#development-commands).
 `c8` uses V8 coverage, so the `--strip-types` source is instrumented without a
 build step, and the runner relies on the `.ts` import-extension convention (see
@@ -96,7 +96,7 @@ import { LspSession } from "#test-utils/lsp-completion.ts";
   loader needed.
 - The helper uses `node:` builtins (it drives a language server), so
   `import/no-nodejs-modules` is off for `src/util/__tests__/**` in
-  `.oxlintrc.json` — the same exception the old `scripts/**` scope carried.
+  `.oxlintrc.json` — the same exception the `scripts/**` scope carries.
 - Helpers carry no library coupling: their tests probe in-memory documents
   whose contextual types are written inline, so only the helper's own contract
   (marker handling, position, label extraction) is under test. A test that