restart_app 1.9.0

Upgrade notes: Android minSdk rises from 16 to 21 and the Android toolchain moves to Java 17, AGP 8.1.4 and Kotlin 2.0.21; the iOS CocoaPods minimum rises from 11.0 to 12.0. Apps on older toolchains must update their build setup before upgrading. On web, the default restart now reloads the current page instead of navigating to the site origin root; pass webOrigin to keep the previous behavior.

• Changed the web default restart to reload the current page, keeping the active route instead of jumping to the origin root; webOrigin still overrides the target
• Fixed Windows so a failed relaunch (for example MSIX/Store-packaged apps) returns a RESTART_FAILED error instead of a false success; the new instance now starts suspended and only resumes after the result is delivered
• Made unknown platform response modes fall back to the requested mode instead of silently reporting platformDefault
• Hardened result parsing so non-string code, message, and reason values can never throw
• Added web plugin tests that cover the full method-channel contract, plus a Chrome test step in CI
• Added CI restart proofs that build, run, and verify a real process restart on Linux, Windows, and macOS runners
• Added explicit engine restart, force-kill restart, and webOrigin buttons to the example app
• Fixed the example Android manifest so url_launcher link checks pass on Android 11+ (package visibility <queries>)
• Removed the redundant Android finishAffinity() after the relaunch intent, which made ActivityTaskManager log a "Duplicate finish request" on every default restart
• Prepared the Android build for Flutter's Built-in Kotlin: the Kotlin Gradle Plugin is now applied only on AGP versions below 9, with modernized Kotlin 2.0 tooling
• Aligned the iOS CocoaPods minimum with Swift Package Manager at iOS 12
• Made the macOS handler hop to the main thread explicitly before touching AppKit