feat(engagement): the in-app channel, core and web (engagement Phase 7)

ENGAGEMENT.md Phase 7. `user_notifications`, the in-app DeliveryChannel, the
four inbox routes, and the web surface — plus the two pieces earlier phases
assigned here that Phase 7's own acceptance line omits.

Four decisions settled by the org lead before any code:

1. `inapp` defaults to `instant` — the only channel that does. Push wakes a
   device somebody is holding and email leaves the building, so both are asked
   for; an inbox item is a row on a page the user chose to open. Left `off` the
   channel ships dead.
2. The phase takes push's `deliver` (§2603) and the web per-channel preferences
   screen (Phase 3's as-built), neither of which its own bullets mention.
3. The inbox takes `/auth/me/notifications` and `/account/notifications`; the
   preferences screen moves to `…/settings`. The plain word belongs to the
   content, which is what the bell opens.
4. `ctx.inbox.push` honours the user's in-app preference when `triggerId` names
   a registered trigger, and writes when it does not.

Server
- `user_notifications` + `model/userNotifications/`. The dedupe UNIQUE is scoped
  to the USER, narrower than the outbox's `(rule, user, channel)`: an inbox has
  no channel dimension, so two rows for one event would be one item shown twice.
- `engagement/inappChannel.js` — renders by block ROLE (first heading → title,
  first button → url, the rest → body) and inserts. `pushChannel.js` — a
  content-free `{stream, ref}` tickle whose ref deep-links the inbox row.
- `engine.liveChannels` orders `inapp` first (`CHANNEL_ORDER`) so that ref
  resolves on the first sweep. An ordering, not a dependency.
- `templates.renderInappByKey` + `resolveTemplate` extracted from `renderByKey`,
  so both channels take the same fallback chain.
- `inapp.event` seed → seedVersion 2: it named `body`/`url`, which nothing
  supplies. Renamed to the structural vocabulary the projection fills in.
- `utils/userNotificationsPrune.js` — nightly, READ items only, horizon in
  `settings.user_notifications_retain_days` (default 90).
- `GET /auth/me/notifications`, `…/unread-count`, `POST …/:id/read`,
  `POST …/read-all`. Swagger + route manifest + four component schemas.

Web
- `NotificationBell` in all three headers, polling its badge once a minute and
  pausing while the tab is hidden. `PlayerInbox` at `/account/notifications`.
- The preferences screen becomes a channel matrix over
  `/auth/me/notifications/channels` — a strict superset of the push-only stream
  list it replaces. The two legacy endpoints are untouched, so the shipped
  Android app keeps its wire shape.
- Staff get the same two screens at `/admin/notifications…`: `RequirePlayer`
  keeps them out of `/account`, so without this the inbox was unreachable for
  every non-player account. `lib/notificationPaths.js` is the one mapping.

Verified: 28 new server tests (5 of them against a real MariaDB, for the three
index/statement properties that are a server contract rather than a reading of
this code) + 3 client. Server suite green, client 327 green. A live rig walked
the whole path: two rules on one event produced three outbox rows and exactly
one inbox item, the tickle carried `ref: notification:2`, and the retention
sweep dropped an aged read row while keeping an equally aged unread one.

Docs: RunicGateway/docs#TBD, RunicGateway/runicgateway.com#TBD

Co-Authored-By: Claude <noreply@anthropic.com>

client/src/routes/player/PlayerPortalLayout.jsx

@@ -2,6 +2,7 @@ import { useMemo } from 'react'
 import { NavLink, Navigate, Outlet, useNavigate, useLocation } from 'react-router-dom'
 import MoonDot from '../../components/MoonDot.jsx'
 import BrandLogo from '../../components/BrandLogo.jsx'
+import NotificationBell from '../../components/NotificationBell.jsx'
 import { useAuth } from '../../contexts/AuthContext.jsx'
 import { useSite } from '../../contexts/SiteContext.jsx'
 import { applyNavOverrides } from '../../lib/navOverrides.js'
@@ -36,6 +37,9 @@ function Icon({ children, size = 16 }) {
 const IconGear = () => <Icon><circle cx="12" cy="12" r="3" /><path d="M12 2v3M12 19v3M2 12h3M19 12h3M4.9 4.9l2.1 2.1M17 17l2.1 2.1M19.1 4.9L17 7M7 17l-2.1 2.1" /></Icon>
 const IconShield = () => <Icon><path d="M12 3l7 3v5c0 5-3.5 8-7 10-3.5-2-7-5-7-10V6z" /><path d="M9 12l2 2 4-4" /></Icon>
 const IconBell = () => <Icon><path d="M18 8a6 6 0 10-12 0c0 7-3 9-3 9h18s-3-2-3-9" /><path d="M13.7 21a2 2 0 01-3.4 0" /></Icon>
+// The settings row's own icon: a bell would make the two rows read as the same
+// destination twice, which is exactly the confusion the split was meant to end.
+const IconBellGear = () => <Icon><path d="M18 8a6 6 0 10-12 0c0 7-3 9-3 9h11" /><circle cx="18" cy="18" r="3" /><path d="M18 14v1M18 21v1M14 18h1M21 18h1" /></Icon>
 
 // Exported because Admin -> Navigation edits this list. It stays declared here;
 // the editor may only relabel, reorder and hide what it finds (§7). No CORE row
@@ -48,7 +52,8 @@ const IconBell = () => <Icon><path d="M18 8a6 6 0 10-12 0c0 7-3 9-3 9h18s-3-2-3-
 // with `order: 0`.
 export const NAV = [
   { to: '/account/appeals', label: 'Appeals', icon: IconShield },
-  { to: '/account/notifications', label: 'Notifications', icon: IconBell },
+  { to: '/account/notifications', label: 'Notifications', end: true, icon: IconBell },
+  { to: '/account/notifications/settings', label: 'Notification settings', icon: IconBellGear },
   { to: '/account', label: 'Account', end: true, icon: IconGear },
 ]
 
@@ -59,6 +64,7 @@ const TITLES = {
   '/account': 'Account',
   '/account/appeals': 'Appeals',
   '/account/notifications': 'Notifications',
+  '/account/notifications/settings': 'Notification settings',
 }
 
 function moduleTitle(baseNav, pathname) {
@@ -186,9 +192,12 @@ export default function PlayerPortalLayout() {
           <h1 className="display" style={{ margin: 0, fontSize: '1.5rem', color: 'var(--head)' }}>
             {title}
           </h1>
-          <a href="/" style={{ color: 'var(--accent)', textDecoration: 'none', fontSize: '0.84rem', fontFamily: 'var(--sans)' }}>
-            ← Site
-          </a>
+          <div style={{ display: 'flex', alignItems: 'center', gap: 12 }}>
+            <NotificationBell />
+            <a href="/" style={{ color: 'var(--accent)', textDecoration: 'none', fontSize: '0.84rem', fontFamily: 'var(--sans)' }}>
+              ← Site
+            </a>
+          </div>
         </header>
 
         <div style={{ flex: 1, padding: '30px 32px 60px', maxWidth: 900, width: '100%' }}>