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 `///`).

place_tracker/lib/place_details.dart

@@ -240,10 +240,9 @@ class _Reviews extends StatelessWidget {
           ),
         ),
         Column(
-          children:
-              StubData.reviewStrings
-                  .map((reviewText) => _buildSingleReview(reviewText))
-                  .toList(),
+          children: StubData.reviewStrings
+              .map((reviewText) => _buildSingleReview(reviewText))
+              .toList(),
         ),
       ],
     );
@@ -308,17 +307,16 @@ class _StarBar extends StatelessWidget {
   Widget build(BuildContext context) {
     return Row(
       mainAxisAlignment: MainAxisAlignment.center,
-      children:
-          List.generate(maxStars, (index) {
-            return IconButton(
-              icon: const Icon(Icons.star),
-              iconSize: 40,
-              color: rating > index ? Colors.amber : Colors.grey[400],
-              onPressed: () {
-                onChanged(index + 1);
-              },
-            );
-          }).toList(),
+      children: List.generate(maxStars, (index) {
+        return IconButton(
+          icon: const Icon(Icons.star),
+          iconSize: 40,
+          color: rating > index ? Colors.amber : Colors.grey[400],
+          onPressed: () {
+            onChanged(index + 1);
+          },
+        );
+      }).toList(),
     );
   }
 }