news: the adventure page gets something that's actually happening

Every dispatch Pete publishes is an accomplishment — a death, a clear, a
milestone — and an accomplishment is a newspaper clipping the moment it lands.
No refresh interval fixes that. So the page never felt alive, and it never was
going to.

The board is the other kind of thing: state that is currently true. gogobee
pushes the whole roster, we replace ours with it, and it renders above the
clippings. An open tab re-polls so it keeps telling the truth.

Replace, never merge: anyone gogobee omits (opted out, no character) drops off
the public page. That omission IS the opt-out — a standing row showing class,
level and zone names the player anyway, so "an adventurer" would have been a fig
leaf.

The snapshot time lives in its own row, because an empty board is ambiguous:
nobody playing, or gogobee stopped talking to us. The page has to tell those
apart — one is a quiet realm, the other is a board that lies confidently, which
is worse than one that admits it lost the wire.

Also teaches Pete "departure", so a bored adventurer letting itself out is news.

internal/web/adventure.go

@@ -192,6 +192,8 @@ func advEventMeta(eventType string) (label, emoji string) {
 		return "Milestone", "🏅"
 	case "retreat":
 		return "Pulled out", "🎒"
+	case "departure":
+		return "Wandered off", "🚪"
 	}
 	return "Dispatch", "📣"
 }
@@ -392,6 +394,13 @@ func renderAdventure(f AdvFact) (headline, lede string, ok bool) {
 		return fmt.Sprintf("%s backed out of %s.", f.Subject, f.Zone),
 			fmt.Sprintf("%s turned around %s — %s got the better of them this time%s, and they made the call to walk out rather than push it. Everybody came home breathing, which is the bit that counts. That dungeon'll still be there next week.",
 				f.Subject, howFar, f.Zone, atLevel), true
+	case "departure":
+		// A bored adventurer let themselves out. Nobody sent them — they got
+		// restless waiting on a player who wasn't coming, took the cheap supplies
+		// they could afford, and went. Pete plays it straight and a little fond;
+		// the joke tells itself, and the player it's about may well be reading.
+		return fmt.Sprintf("%s got bored and left without waiting.", f.Subject),
+			fmt.Sprintf("No orders, no escort, no fuss — %s packed the cheapest kit on the shelf and set off into %s%s. Nobody told them to. Nobody talked them out of it either. We'll let you know how it goes.", f.Subject, f.Zone, atLevel), true
 	case "arrival":
 		return fmt.Sprintf("Welcome to the realm, %s!", f.Subject),
 			fmt.Sprintf("A new %s just walked through the gates. Say hello if you see them out there.", f.ClassRace), true