fix: touch scaling, sandbox, and output scale

[mister-teddy]

Summary

Fixes Android touch/scale behavior and related launch issues for the local desktop runtime.

Details

• Uses Android density for guest UI scaling while keeping the parent Wayland output scale in physical pixels.
• Updates touch gesture handling to better match Android conventions.
• Adds/refreshes Chromium/Electron no-sandbox handling for Android.
• Updates offline documentation/manual behavior and related developer/user docs.

Validation

• cargo fmt --check
• git diff --check --cached
• cargo check --target aarch64-linux-android --lib

The Android library check passes with existing warnings in patched Smithay and src/android/utils/webview.rs.