adventure: bored adventurers go into dungeons on their own

A player who stops tending their adventurer doesn't stop having one. After
24h with no action against Adventure, the character gets restless and leaves
on an expedition by itself: the easiest zone its level band allows, the
cheapest supplies it can afford, and whatever gear was already on the rack.

Everything downstream of the start was already autonomous — the autopilot
walks rooms, drives elite and boss fights on the turn engine, camps, harvests
and picks forks. The only thing that ever needed a human was `!expedition
start`, so that's all this adds: a 30m ticker plus a clock.

It never buys or equips anything, and that is the whole mechanic: a neglected
adventurer grinds half-starved runs on rusting gear and comes home taxed. The
prodexercise killed an L4 mage four rooms in on its first run.

The clock is a new column. Every existing timestamp is unusable: last_active_at
is auto-bumped by saveAdvCharacter (the autopilot would refresh a bored
character's own idle clock), loadAdvDailyActivity counts the autopilot's own
expedition logs, and user_stats.updated_at is chat presence, not a game action.
last_player_action_at is written only by markPlayerAction, from a real player
action against Adventure — any interface, not just Matrix.

Raid zones (raidContentWarning: the party-tuned T5 bosses with a 0% solo clear)
are avoided while anything else is in band. At L13+ they're all that's left, and
the adventurer goes in anyway and loses. That's intended.

dnd_expedition.boredom + isBoredomDriven stop a run nobody asked for from
shielding an absent player from the idle reaper or holding their streak. A
manually-started expedition still holds it while the autopilot walks it.

Robbie visits and pays silently for idle players — he was going to file a daily
public bulletin about people who stopped playing weeks ago.

Note for anyone touching the time-scanning queries here: modernc.org/sqlite
rebuilds a time.Time from the column's declared type, and COALESCE()/MAX() erase
it. playerIsIdle fails open, so a broken scan there declares the whole server
idle. Both it and lastExpeditionByZone select declared columns and fold in Go,
and the tests seed real rows so the scan actually executes.

internal/plugin/adventure_scheduler.go

@@ -405,8 +405,9 @@ func (p *AdventurePlugin) midnightReset() error {
 		return fmt.Errorf("load chars: %w", err)
 	}
 
-	today := time.Now().UTC().Format("2006-01-02")
-	yesterday := time.Now().UTC().Add(-24 * time.Hour).Format("2006-01-02")
+	now := time.Now().UTC()
+	today := now.Format("2006-01-02")
+	yesterday := now.Add(-24 * time.Hour).Format("2006-01-02")
 
 	// Unified activity oracle — same source the daily report uses. Unions
 	// adventure_activity_log + dnd_zone_run + dnd_expedition_log, so
@@ -457,25 +458,32 @@ func (p *AdventurePlugin) midnightReset() error {
 			continue
 		}
 
-		// Activity happened on the player's behalf without an explicit tap —
-		// autopilot walked rooms, expedition log gained beats, a fight session
-		// is still locked open. Hold the streak: no bump, no shame, no decay.
-		// The player engaged earlier to kick this off; autopilot is a feature,
-		// not a way to game streaks, and absence of taps shouldn't strip
-		// progress they earned through real play.
-		if len(todayActs[char.UserID]) > 0 || len(yesterdayActs[char.UserID]) > 0 {
-			continue
-		}
-		// Safety net for live state the activity logs don't reflect yet
-		// (e.g. an active expedition that's been quiet today, or a combat
-		// session locked open across midnight without a log append).
-		if exp, err := getActiveExpedition(char.UserID); err != nil {
-			slog.Warn("adventure: failed to check active expedition for idle reaper", "user", char.UserID, "err", err)
-		} else if exp != nil {
-			continue
-		}
-		if hasActiveCombatSession(char.UserID) {
-			continue
+		// Every hold below rests on one premise: the player engaged earlier to
+		// kick this off, so the autopilot finishing the job shouldn't cost them
+		// their streak. A boredom expedition has no such origin — nobody kicked
+		// it off, and its player still hasn't come back. It earns them nothing
+		// and shields them from nothing (gogobee_boredom_plan.md §6).
+		if !isBoredomDriven(char.UserID, now) {
+			// Activity happened on the player's behalf without an explicit tap —
+			// autopilot walked rooms, expedition log gained beats, a fight session
+			// is still locked open. Hold the streak: no bump, no shame, no decay.
+			// The player engaged earlier to kick this off; autopilot is a feature,
+			// not a way to game streaks, and absence of taps shouldn't strip
+			// progress they earned through real play.
+			if len(todayActs[char.UserID]) > 0 || len(yesterdayActs[char.UserID]) > 0 {
+				continue
+			}
+			// Safety net for live state the activity logs don't reflect yet
+			// (e.g. an active expedition that's been quiet today, or a combat
+			// session locked open across midnight without a log append).
+			if exp, err := getActiveExpedition(char.UserID); err != nil {
+				slog.Warn("adventure: failed to check active expedition for idle reaper", "user", char.UserID, "err", err)
+			} else if exp != nil {
+				continue
+			}
+			if hasActiveCombatSession(char.UserID) {
+				continue
+			}
 		}
 
 		// Truly idle — shame DM + streak halve.