feat(core): back button event on Android, closes #8142

[tomerqodo]

Benchmark PR from qodo-benchmark#162

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Note

Introduces Android back-button handling and supporting infrastructure.

• Adds Android AppPlugin that intercepts back presses (navigates webview back or finishes activity) and exposes an exit command; TauriActivity now enables back navigation
• Wires Android plugin in Rust app plugin setup and extends core app permissions with register_listener/remove_listener
• Adds app.onBackButtonPress to @tauri-apps/api and updates global bundle to support plugin listener registration/removal
• Enhances Android Plugin base to support event listeners (registerListener, removeListener, hasListener)
• Bumps wry to 0.53.4 and updates related lockfile entries; minor cleanup in Android path resolver

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Stale listeners cause back button to stop working

Medium Severity

After a webview page reload or navigation, JS-registered listeners become stale but remain in the Kotlin listeners map. When handleOnBackPressed runs, hasListener(BACK_BUTTON_EVENT) returns true for these dead channels, so trigger() is called instead of the default back navigation. Since the JS callback no longer exists, the event is lost and the back button appears to do nothing. The load() method doesn't clear listeners, and there's no page lifecycle hook to clean them up.