Dart 3.9 / Flutter 3.35 [first LLM release] (#2714)

I got carried away with Gemini and basically rewrote CI and the release
process for the new LLM reality. This work was largely completed by
Gemini.

- Bump all SDK versions to the current beta (3.9.0-0)
- Run `flutter channel beta`
- Wrote `ci_script.dart` to replace the bash scripts
- Converted repository to pub workspace #2499 
- Added llm.md and release.md
- Added redirect for deprecated Samples Index

## Pre-launch Checklist

- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
- [x] I signed the [CLA].
- [x] I read the [Contributors Guide].
- [x] I have added sample code updates to the [changelog].
- [x] I updated/added relevant documentation (doc comments with `///`).

animations/test/misc/card_swipe_test.dart

@@ -24,7 +24,10 @@ void main() {
       await tester.pumpAndSettle();
 
       // Check if removed properly.
-      expect(tester.widgetList(find.byType(Card)).length, lessThan(totalCards));
+      expect(
+        tester.widgetList(find.byType(Card)).length,
+        lessThan(totalCards),
+      );
     });
 
     testWidgets('All cards swiped out', (tester) async {
@@ -36,7 +39,10 @@ void main() {
       // Swipe out all cards.
       for (var i = 0; i < totalCards; i++) {
         // Swipe out one by one.
-        await tester.drag(find.byType(Card).last, const Offset(100.0, 0.0));
+        await tester.drag(
+          find.byType(Card).last,
+          const Offset(100.0, 0.0),
+        );
         await tester.pumpAndSettle();
       }
 

animations/test/misc/carousel_test.dart

@@ -18,7 +18,11 @@ void main() {
       expect(imageList.length, 2);
 
       // Swipe the Carousel.
-      await tester.fling(find.byType(CarouselDemo), const Offset(-400, 0), 800);
+      await tester.fling(
+        find.byType(CarouselDemo),
+        const Offset(-400, 0),
+        800,
+      );
       await tester.pumpAndSettle();
 
       // Get the images available on the screen after swipe.

animations/test/misc/expand_card_test.dart

@@ -22,7 +22,10 @@ void main() {
 
       // The size of ExpandCard must change once tapped.
       // The initialSize should be less than current ExpandCard size.
-      expect(initialSize, lessThan(tester.getSize(find.byType(ExpandCard))));
+      expect(
+        initialSize,
+        lessThan(tester.getSize(find.byType(ExpandCard))),
+      );
     });
 
     testWidgets('ExpandCard changes image on tap', (tester) async {

animations/test/misc/focus_image_test.dart

@@ -33,7 +33,9 @@ void main() {
       expect(finalSize, greaterThan(initialSize));
     });
 
-    testWidgets('Final inkwell on tap goes back to the grid', (tester) async {
+    testWidgets('Final inkwell on tap goes back to the grid', (
+      tester,
+    ) async {
       await tester.pumpWidget(createFocusImageScreen());
 
       // Tap on the ink well at index 0.

animations/test/misc/hero_animation_test.dart

@@ -58,7 +58,9 @@ void main() {
       // Final color should not be same as initial color.
       expect(
         (finalContainer.decoration as BoxDecoration).color,
-        isNot(equals((initialContainer.decoration as BoxDecoration).color)),
+        isNot(
+          equals((initialContainer.decoration as BoxDecoration).color),
+        ),
       );
     });
 
@@ -66,7 +68,9 @@ void main() {
       await tester.pumpWidget(createHeroAnimationDemoScreen());
 
       // Get the initial Screen.
-      final initialScreen = tester.firstWidget(find.byType(HeroAnimationDemo));
+      final initialScreen = tester.firstWidget(
+        find.byType(HeroAnimationDemo),
+      );
 
       // Tap on the GestureDetector.
       await tester.tap(find.byType(GestureDetector));