Manual recreation of https://github.com/flutter/flutter/pull/148911
Entire PR is just the output of
```
flutter update-packages --force-upgrade
```
followed by (run from the root of the flutter repo)
```
find . -type d -name 'android' | dart dev/tools/bin/generate_gradle_lockfiles.dart --no-gradle-generation --no-exclusion
```
Upgrades agp versions and lockfiles for `dev/`. Also changes the lockfile generation script to represent the newer form of the `settings.gradle` template, and therefore also propagates these changes.
~~Potentially related to https://github.com/flutter/flutter/issues/134419~~, but worth doing anyways. (not actually related)
