Android TV can't be signed in from a nearby phone after its session expires

[Quick104]

A nearby phone or tablet only offers to set up an Android TV while the TV shows its server-setup screen. When the TV's session expires, or the user switches to a saved server that has no sign-in, the TV shows its sign-in screen instead, and no phone offers to sign it back in. The only ways back are scanning the QR code, which opens the web approval page and needs a separate web sign-in, or typing a password with the remote. Sign Out isn't affected, because it returns to server setup, which advertises.

Why

• TvServerSetupScreen starts and stops the pairing advertiser (TvServerSetupScreen.kt). TvLoginScreen doesn't advertise.
• The advertiser always sends st=setup (AndroidTvModule.kt). Its comment explains why: advertising login made the TV invisible to iPhones, whose card only offers setup TVs.
• An expired session navigates to TvRoute.Login (TvAppNavigation.kt). Sign Out navigates to server setup (lines 733-741).

Expected

A signed-out Android TV on its sign-in screen advertises login and gets the same offer from a signed-in phone or tablet on the same network: sign it in, confirm the code, approve. The phone offers it only when it holds the server the TV is signed out of, and skips the server chooser.

Notes

• Needs the iOS side first (Apple TV can't be signed in from a nearby iPhone after Sign Out or an expired session silo-apple#552), so iPhones accept login TVs before any TV advertises it.
• The phone has to know which server the TV wants, so the TXT record or hello needs to carry the server identity from GET /api/v2/system/identity. That is an additive protocol change, to agree with silo-apple.
• The Android phone doesn't check st today; it offers the first TV it hasn't dismissed (HomeScreen.kt). A login TV would get the full server chooser.
• Related issue: [v1] TV client sign-in & onboarding silo-server#1192. Its AC2 covers TVs awaiting setup; this extends the same offer to signed-out TVs.

AI disclosure

• Harness: T3 Code (Claude Code agent harness)
• Tool(s): Claude Code, GitHub CLI
• Model(s): claude-opus-5-5
• Involvement: AI-drafted at the maintainer's request, from reading the code on main at c38fb93; not reproduced on a device
• Adversarial review: n/a