Fix iOS AppIcon and prepare build 43

[denuoweb]

What changed

• replace the obsolete iOS placeholder icon with an opaque 1024×1024 AppIcon derived exactly from the canonical Android/Google Play artwork
• increment the iOS/App Store build from 42 to 43 across the Xcode project, Info.plist, project definition, validator, checklist, and release documentation
• strengthen preflight validation for the canonical icon, every version/build declaration, archived bundle identity, export-compliance value, and compiled asset catalog
• commit the verified live Release-simulator App Store screenshots and provenance manifest

Why

Build 42 was already accepted by App Store Connect, so its icon cannot be replaced in place. The initial iOS shell retained an obsolete placeholder icon. Build 43 is the immutable follow-up that gives the App Store build the same production artwork as Android and prevents a mismatched archive from uploading.

Impact

The application runtime is unchanged. The affected-target classifier selects only the macOS iOS gate (rust=false, android=false, ios=true). After this PR passes CI and is merged, the protected TestFlight workflow can sign and upload 0.5.0 (43).

Checks

• python3 dist/app-store/validate.py
• ./scripts/check-version-consistency.sh
• python3 -m unittest tests.test_ios_screenshot_tools
• python3 scripts/test_select_ios_simulator.py
• shellcheck scripts/run-ios-gate.sh scripts/upload-ios-testflight.sh
• bash -n scripts/run-ios-gate.sh scripts/upload-ios-testflight.sh
• git diff --check
• icon dimensions, opacity, sRGB color space, and exact SHA-256 verified
• live screenshot dimensions and artifact digests verified