📝 Sweep doc and formatter drift

README named --experimental-strip-types, which was renamed to
--strip-types. Document the current flag only.

The extension recommendations list is unchanged, but the VSCode section
undercounted it and now matches extensions.json. The per-language
formatter blocks in .vscode/settings.json stay (they keep a user's
local formatter settings from overriding the project's) and gain the
JSX/TSX language ids to match what oxfmt and the lefthook glob cover.

.vscode/settings.json

@@ -3,10 +3,18 @@
         "editor.defaultFormatter": "oxc.oxc-vscode",
         "editor.formatOnSave": true
     },
+    "[typescriptreact]": {
+        "editor.defaultFormatter": "oxc.oxc-vscode",
+        "editor.formatOnSave": true
+    },
     "[javascript]": {
         "editor.defaultFormatter": "oxc.oxc-vscode",
         "editor.formatOnSave": true
     },
+    "[javascriptreact]": {
+        "editor.defaultFormatter": "oxc.oxc-vscode",
+        "editor.formatOnSave": true
+    },
     "[json]": {
         "editor.defaultFormatter": "oxc.oxc-vscode",
         "editor.formatOnSave": true