chat notifications reach the phone, on the same rule as the bell

the browser bell and phone push are now two subscribers to one signal. both
ask shouldNotify(); neither owns the rule.

deliberately a second subscriber rather than a branch inside notify-delivery.
the two channels share only the question "does this account want to hear about
this" — the browser needs an open tab and sends the chat's real title over a
loopback socket on the owner's own tailnet, the phone needs no tab and must
send NO title, because that hop goes through apple. one function doing both
means an `if (isPush)` at every step, and the first thing to go wrong is a
title leaking because the branch was missed in one place.

two codes, officer/core:chat.turn-ended and chat.input-needed. the route is
written out with its scheme rather than derived from the target: the hub has
no chat screen — chat is Butler, a sibling app — so these deep-link OUT over
officer-chat://, and two of the suite's twenty-one schemes already break the
officer-<app> pattern (officer-videos, officer-readaloud). deriving that works
until it silently does not.

`thread` interpolates now, so `chat:{id}` groups per conversation. a static
thread forces a choice between "three pings from one chat collapse" and "two
busy chats stay apart", and the wrong answer is that every chat is the same
chat.

dropped officer/core:agent: chat.turn-ended supersedes it and its route
pointed at officer://chat/{id}, a hub screen that does not exist.

the banner cannot name which conversation. a chat's title is content and
content does not travel; it says what happened, and tapping opens the chat,
which is where the name lives.

src/server.tsx

@@ -18,6 +18,7 @@ import { isTokenBlacklisted, getUserById } from 'officerdb';
 import { terminalWebsocket } from './servers/api/terminal/websocket';
 import { chatWebsocket } from './servers/api/chat/websocket';
 import { chatNotifyWebsocket } from './servers/api/chat/notify-delivery';
+import { registerChatPushNotifications } from './servers/api/chat/notify-push';
 import { taskRunnerWebsocket } from './servers/api/tasks/task-executor';
 import { pipelineWebsocket } from './servers/api/tasks/pipeline-executor';
 // import { desktopWebsocket } from './servers/api/desktop/websocket';
@@ -160,6 +161,11 @@ assertPermissionTotality({
   wsProviders: Object.keys(handlers),
 });
 
+// Chat's phone channel. Subscribes to the same signal the browser bell uses and asks the same question;
+// it just answers it into APNs/FCM instead of a websocket. Registered here, and explicitly, because a
+// module whose only job is a side effect is one an import sweep quietly deletes.
+registerChatPushNotifications();
+
 // That the working directory is the repo, because every path derives from its parent. First of the three,
 // since a wrong answer here makes the other two check the wrong files.
 assertInstallLayout();