zones: make locked doors openable and stop autopilot stalling on them

Locks were fully implemented as pass/fail gates and nothing else. A
Perception or stat check rolls once per (run, edge), seeded so it can't
be reload-scummed — that half shipped in G5, the counterweight never did.
A bad roll simply deleted a branch of the graph for the rest of the run,
worst for a solo low-WIS character who quietly loses routes they never
learn existed. Three changes, one theme: a die roll should not be able to
permanently wall a player.

Party's best stat answers the check. evaluateEdgeLock read only the
acting character's mods, which made a party's rogue and its hired scout
decorative at every lock. Fold the whole roster — Pete included, since
excluding him would make hiring a scout worth less than the coins it
costs — and credit whoever got it open in the fork menu.

Thieves' tools as the escape hatch. A utility item (not a ConsumableDef,
or the fight engine would spend them for you) sold on Luigi's supplies
shelf, consumed by `!zone unlock <n>`. Deliberately not a skeleton key:
tools answer the two dice-driven locks only. A key lock is a quest token,
a level-min lock is progression, a region-clear lock is structure — none
of those are "you rolled badly", so none of them are pickable.

Autopilot picks a route instead of parking. The fork timeout was 8h,
which reads as "the player gets first say" and behaves as "the expedition
stops for a third of a day, at every fork" — a multi-day expedition
crosses a lot of forks. 30m keeps a genuine first say for anyone at the
keyboard. It now ranks by unvisited-then-edge-weight rather than taking
whatever the graph author happened to list first, spends tools when every
route is locked, and backtracks a room when it can't do even that, rather
than idling into the 24h reaper and losing the player days of progress to
a roll they never saw.

Sim A/B, same seeds, 90 runs/arm: 43.3% -> 42.2% clear, a single run
flipping and well inside the documented noise floor. A party+companion+pet
arm runs 31/32 clean through the new roster-folding path.

internal/plugin/dnd_zone_cmd.go

@@ -53,6 +53,9 @@ func (p *AdventurePlugin) handleDnDZoneCmd(ctx MessageContext, args string) erro
 		// fork pending) the handler short-circuits with a friendly
 		// message — see zoneCmdGo for the full surface.
 		return p.zoneCmdGo(ctx, rest)
+	case "unlock", "pick", "force":
+		// Spend thieves' tools on a fork option a failed check closed.
+		return p.zoneCmdUnlock(ctx, rest)
 	case "status", "info":
 		return p.zoneCmdStatus(ctx)
 	case "map", "m":
@@ -83,6 +86,7 @@ func zoneHelpText() string {
 	b.WriteString("`!zone map` — show the room layout\n")
 	b.WriteString("`!zone advance` — resolve the current room and move on\n")
 	b.WriteString("`!zone go <n>` — at a fork, take path #n\n")
+	b.WriteString("`!zone unlock <n>` — spend thieves' tools to open a path you couldn't\n")
 	b.WriteString("`!revisit <n>` — walk back to a room you've already cleared\n")
 	b.WriteString("`!zone abandon` — end the active run (no rewards)\n")
 	b.WriteString("`!zone taunt` — poke TwinBee (they'll remember)\n")