bvandeusen
81695fa0c8
Closes M12. The phone can now notice that its server has a newer build and install it, instead of the operator copying an APK to a device by hand. **A PackageInstaller session, not an install intent.** The obvious route — ACTION_VIEW on the APK — is exactly what on-device install heuristics are tuned against, and it is what produced the "bypassing Android security" warning on Minstrel (Scribe note 2437). It also never tells the OS that this app is the legitimate updater of its own package, and it returns nothing: a failed install is indistinguishable from someone dismissing the dialog. The session says who is doing what, and on Android 12+ declares no user action required — which, with UPDATE_PACKAGES_WITHOUT_USER_ACTION, removes the confirmation entirely on the UPDATE path. Only there: Android will not let an app quietly put a NEW package on a device, which is right. It also only applies when the new build carries the same signing key as the installed one, which is why signing had to land first. Two things from that research deliberately NOT done: `setRequestUpdateOwnership` was chased and turned out to be a red herring, and REQUEST_INSTALL_PACKAGES is not the differentiator either — Mihon declares it too. The mechanism was the whole difference. **The outcome comes back.** `commit` takes an IntentSender and the result lands at `UpdateReceiver`, so a failure can be shown rather than guessed at, and STATUS_PENDING_USER_ACTION is handled — that is the ordinary path below API 31 and still possible above it, since the OS is entitled to ask anyway. Someone declining is reported as no error at all: calling a deliberate choice a failure is how an app sounds broken when it is not. **The network work stays in Rust.** Two FFI additions — `clientUpdate` and `downloadClientUpdate` — because the device token lives in the core, and pulling it into Kotlin to make an HTTP call would spread the one secret this app holds across two languages for nothing. The core also owns the comparison, so the rule "version CODE decides, never the name" lives in the layer that has to get it right for every surface. The download is streamed to disk, not buffered: 55 MiB in memory on a phone is how an update gets killed halfway through. It lands in `update.apk.part` and is renamed only once size and sha256 both match, so an interrupted download can never be mistaken for a finished one. The digest is not a trust anchor — the signature is, and Android checks it — but it catches a truncated transfer before the installer is bothered with it. The advertised path is joined to the base URL this device is LINKED to rather than followed as given, so a server cannot point the download at a host nobody agreed to. **Updates are linked-only, and it says so.** An unlinked install has no update path, so it gets one sentence explaining where updates come from rather than a Check button that silently finds nothing — the same lesson as the desktop's unlink copy (issue 2110). And the "install unknown apps" grant is asked for BEFORE downloading, so nobody spends 55 MiB to be told no. Every Android API here was read out of `android-36/android.jar` with javap first, and the two new FFI methods out of freshly generated bindings, rather than recalled: `suspend fun clientUpdate(installedVersionCode: Long): ClientUpdate?` and `downloadClientUpdate(destPath: String)`. Also fixes `check-symbols.py`, which reported four false positives on `UpdateOutcome.Result` — its object-member index collected functions and properties but not nested TYPES, and a data class inside an object is an ordinary member.