Related to flutter/flutter#183099

Allow users to specify onExit as optional

## Pre-Review Checklist

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Adds some optional behaviors needed to use the tool in flutter/core-packages:
- Allow setting a min Dart version rather than a min Flutter version at the repo level
- Don't require .ci.yaml to be present when batch config isn't used (since that repo currently doesn't use LUCI)

)

Google Maps SDK 8.4 didn't include a privacy manifest, just instructions for clients to download and manually add one. Rather than push that requirement onto plugin clients, we duplicated all of the relevant manifest entries into the plugin's manifest.

[Starting with 9.0.0](flutter/flutter#146838 (comment)) the Google Maps SDK includes its own manifest, so we no longer need to bundle it ourselves when we know that the SDK is 9+. Since that's the case for the SDK-specific copies of the implementation package, we can remove it there, while leaving it in `google_maps_flutter_ios` (which can still resolve to 8.4).

Fixes flutter/flutter#146838

## Pre-Review Checklist

[^1]: Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling.

flutter/flutter@f3a4b98...c8f2f16

2026-05-27 98614782+auto-submit[bot]@users.noreply.github.com Reverts "[Flutter GPU] Add explicit draw counts (#186639)" (flutter/flutter#187170)
2026-05-27 [email protected] Roll Dart SDK from 7dcea971af6b to f3db7b7d9801 (2 revisions) (flutter/flutter#187144)
2026-05-27 [email protected] [Flutter GPU] Add explicit draw counts (flutter/flutter#186639)
2026-05-27 [email protected] Roll Skia from f9db7748563e to fa944af10f91 (1 revision) (flutter/flutter#187139)
2026-05-27 [email protected] [Flutter GPU] Flutter GPU ShaderLibrary in-place reload for shader hot reload (flutter/flutter#186793)
2026-05-27 [email protected] Roll Skia from a692cbf38952 to f9db7748563e (8 revisions) (flutter/flutter#187135)
2026-05-27 [email protected] Use local semantics tester in Material button tests (flutter/flutter#186667)
2026-05-27 [email protected] Filter out `a: text input` from `team-framework` PR triage  (flutter/flutter#187129)
2026-05-27 [email protected] [Engine] Fix silent buffer mismatch bug in FML Win32 CommandLineFromPlatform (flutter/flutter#187120)
2026-05-27 [email protected] examples: Remove unused parameters (flutter/flutter#185819)
2026-05-27 [email protected] Remove another `String.valueOf` (flutter/flutter#186628)
2026-05-27 [email protected] Print trace when skipping flavor-specific and platform-specific assets (flutter/flutter#187045)
2026-05-26 [email protected] Fix `InteractiveViewer` memory leak from undisposed `CurvedAnimation`s (flutter/flutter#185826)
2026-05-26 [email protected] Fix AccessibilityBridge startup crash on vendor-modified Android (flutter/flutter#184630)
2026-05-26 [email protected] Update data driven fixes docs (flutter/flutter#186217)
2026-05-26 [email protected] Add more 0x0 size tests part10 (flutter/flutter#186201)
2026-05-26 [email protected] Disable spell check for obscured text (flutter/flutter#186329)
2026-05-26 [email protected] [iOS] Migrate VSyncClient and DisplayLinkManager to Swift (flutter/flutter#187001)
2026-05-26 [email protected] [flutter_tools, devicelab] Add safety filesystem guard to tests (flutter/flutter#186748)
2026-05-26 [email protected] Roll Fuchsia Linux SDK from Itd2Jq_ZIABH2rW7B... to k9EizfEGJO4WwQN9-... (flutter/flutter#187115)
2026-05-26 [email protected] Roll Dart SDK from 00e625453c43 to 7dcea971af6b (1 revision) (flutter/flutter#187117)
2026-05-26 [email protected] Remove use of deprecated copy_trees. (flutter/flutter#187091)
2026-05-26 [email protected] Use resolved implementation plugins with SwiftPM (flutter/flutter#187097)
2026-05-26 [email protected] Roll Skia from 27a819894f7c to a692cbf38952 (3 revisions) (flutter/flutter#187109)
2026-05-26 [email protected] Roll Packages from 69cf959 to fc795e5 (4 revisions) (flutter/flutter#187114)
2026-05-26 [email protected] Handle simctl process exceptions during discovery (flutter/flutter#186501)
2026-05-26 [email protected] Clarify precache enabled platforms help (flutter/flutter#186878)
2026-05-26 [email protected] [tool] Refactor artifacts.dart to use enhanced enums and reduce duplication (flutter/flutter#187063)
2026-05-26 [email protected] Build script updates for syncing engine sources and building artifacts on linux-arm64 (flutter/flutter#186917)

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