feat(permissions)!: add a Motion device permission

[decrypto21]

Closes #961

Adds Motion to the device permissions. The user decides once per product (Allow Always, Allow Once, Don't Allow), and the host answers WebKit's motion request from that decision, so iOS no longer shows its own prompt on every launch.

Products call the standard DeviceMotionEvent.requestPermission() on iOS, or requestDevicePermission("Motion") on any host. No platform-specific code.

• Protocol: Motion is appended to HostDevicePermissionRequest, so existing SCALE indexes are unchanged.
• Native: NativeProductExecution::authorize_device_permission resolves a capability the web view gates itself through the product's saved, one-use, or prompted decision. The iOS and Android shells expose it as authorizeDevicePermission.
• iOS: both web view engines implement requestDeviceOrientationAndMotionPermissionFor. The Rust SPA and chat runtimes resolve it through authorizeDevicePermission(.motion); the native runtime uses the existing product permission flow. The prompt, Settings > Apps, and strings cover Motion.
• Android: WebView delivers motion events without asking, so the host answers Motion with Allow Once and no prompt. Nothing is persisted, so no stored grant outlives a settings screen that cannot show it.

The decision is made in the WebKit delegate rather than a container gate because WebKit only consults its delegate during the product's user gesture, and a round trip to the core first would lose it.

Compatibility

• A host built before this change cannot decode Motion and answers requestDevicePermission("Motion") with a malformed-frame error rather than granted: false. Products should treat that error as motion being unsupported. The changeset says so.
• TrUAPIProductExecutionProtocol gains authorizeDevicePermission, so a conformer outside this repo must implement it. The release needs @parity/ios-host in its title.

Known limitation

WebKit caches the motion answer per origin in the web view's data store and has no API to clear it. Within one app launch, a product's first answer therefore applies to later requests: Allow Once lasts until the app is relaunched, and a changed decision takes effect on the next launch.

Testing

• Rust (clippy, fmt, permission tests, a native test that counts the prompt), TS client, and iOS unit tests, including a WKWebView test that requestPermission() resolves from the host's decision.
• iOS simulator on stash.testnet: Allow Always, Don't Allow, and Allow Once on the native runtime, and Allow Always on the Rust runtime, each followed by a relaunch. WebKit's prompt never appeared, and Allow Once prompts again after a relaunch. Re-run at 4a3aeb5 on iPhone 17, iOS 26.5.
• Android emulator on stash.testnet (Android 15, at 4a3aeb5): motion events reach the page and follow values injected with adb emu sensor set acceleration, and requestDevicePermission("Motion") is granted without a prompt, also after a force-stop.

[github-actions]

CI Status: 24 required jobs green, 21 passed and 3 skipped by path filter.

All job results

job	result
android-bindings	success
bundle-size	success
changes	success
changeset-guard	success
cli-package	success
codegen	success
e2e	skipped
explorer	success
headless-install	success
host-android-bindings	success
host-android-detekt	success
host-wasm	success
ios-bindings	success
ios-swift	success
licenses	success
playground	success
provider-android-bindings	skipped
release-guard	success
rust	success
ts-client	success
ts-debugger	success
ts-host	success
wasm-provider	success
workflow-lint	skipped

Signing credentials: failure as of 2026-10-14, a release may fail

_{Commit 28f4620e · run log}

[github-actions]

iOS simulator preview

Built from 6f62619ea, stamped with it in TrUAPICommit.

gh run download 36534625128 --name simulator-preview-6f62619ea
unzip polkadot-app-*.app.zip
xcrun simctl install booted polkadot-app.app
xcrun simctl launch booted io.parity.polkadotapp.develop

Or download it in a browser, which arrives as a zip wrapping
the .app.zip, so it needs unzipping twice.

An arm64 simulator slice, so it needs an Apple Silicon Mac and does not
install on a device. Kept for 14 days, after which the link stops
resolving and a new push rebuilds it.

[github-actions]

This pull request touches an app, which is not built by default. Add a label for each build you want:

• iOS simulator build, ios-simulator-build: builds the iOS app, runs its tests and attaches a build for the iOS Simulator on a Mac.
• iOS device build, ios-device-build: attaches a signed build that installs on a registered iPhone or iPad.
• Android build, android-device-build: attaches an APK that installs on an Android phone or an emulator.

Each starts as soon as it is added and follows the branch from then on.

[github-actions]

Bundle size report

Compared with main at e92f330.

	Raw	Gzip	Brotli
truapi-host	7.89 MiB (+20 B)	5.66 MiB (+25 B)	5.39 MiB (+487 B)
truapi-provider	4.03 MiB	1.27 MiB	960.1 KiB
truapi	6.30 MiB (+241 B)	891.5 KiB (+47 B)	730.0 KiB (+24 B)
Total	18.23 MiB (+261 B)	7.81 MiB (+72 B)	7.04 MiB (+511 B)

WebAssembly modules

	Raw	Gzip	Brotli
truapi-host/wasm/web/truapi_server_bg.wasm	2.78 MiB (+20 B)	992.4 KiB (+25 B)	747.9 KiB (+499 B, +0.1%)
truapi-host/wasm/web/truapi_verifiable_bg.wasm	4.89 MiB	4.64 MiB	4.61 MiB
truapi-provider/truapi_provider_bg.wasm	3.99 MiB	1.26 MiB	952.4 KiB

Changed files (5)

	Raw	Gzip	Brotli
truapi/explorer/codegen/types.js	222.1 KiB (+211 B, +0.1%)	30.8 KiB (+31 B, +0.1%)	24.6 KiB (+24 B, +0.1%)
truapi-host/wasm/web/truapi_server_bg.wasm	2.78 MiB (+20 B)	992.4 KiB (+25 B)	747.9 KiB (+499 B, +0.1%)
truapi/playground/codegen/truapi-dts.js	292.0 KiB (+11 B)	50.5 KiB (+4 B)	40.6 KiB (+16 B)
truapi/generated/types.js	64.3 KiB (+10 B)	7.8 KiB (+6 B, +0.1%)	6.7 KiB (+11 B, +0.2%)
truapi/playground/codegen/services.js	101.5 KiB (+9 B)	15.5 KiB (+5 B)	13.0 KiB (+2 B)

_{Commit: 28f4620}