Select on [dir='rtl'] now that no build rewrites :dir()

Plan step 39 (part 4). With Tailwind gone the Workbench's Vite build
still turns every `:dir(rtl)` into a long `:lang()` list (its own CSS
minifier, not Tailwind's doing — confirmed by rebuilding and grepping
the output). Every RTL mirror rule across the eleven stylesheets that
had one now selects `:is([dir='rtl'], [dir='rtl'] *)` instead, matching
`:dir(rtl)`'s own specificity (one pseudo-class) and its inherited
"this element or a descendant of one carrying the attribute" reach; the
built CSS now keeps the selector as written (no `:lang(` or `:dir(` left).

RTL browser tests drop the `lang="ar"` workaround the old rewrite
needed (ContainmentTest's side-sheet probe, LayoutTest's shared
layoutPage() helper) and set only dir="rtl"; CarouselTest's probe
already did. Feature tests asserting the selector's literal text
(Progress, Overlay, Menu, ListDetail, Icon, Carousel) updated to match.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9

tests/Feature/Components/ProgressTest.php

@@ -113,8 +113,8 @@ it('takes the caller\'s size instead of its own, its class landing on the root u
 it('mirrors the linear indicator in a right-to-left document, unconditionally', function () {
     $css = ComponentStylesheet::read('progress');
 
-    expect($css->declarations('[data-md-progress]:not([data-md-circular]):dir(rtl)'))->toBe(['rotate' => '180deg'])
-        ->and($css->has('[data-md-progress][data-md-circular]:dir(rtl)'))->toBeFalse();
+    expect($css->declarations("[data-md-progress]:not([data-md-circular]):is([dir='rtl'], [dir='rtl'] *)"))->toBe(['rotate' => '180deg'])
+        ->and($css->has("[data-md-progress][data-md-circular]:is([dir='rtl'], [dir='rtl'] *)"))->toBeFalse();
 });
 
 it('follows a value bound in Alpine', function () {