feat(progression): Attempt ledger with terminal-outcome guard (slice 2)

Attempt carries its LevelId so settlement decides First Clear vs Replay
without trusting the caller. Outcome is terminal and refuses to change:
one death costs one life, one completion banks once.

Coins.Zero/Add driven out by the ledger rather than added up front.
21 tests. ADR-0005: Playthrough settles Attempts, has no LoseLife.

progression/AttemptOutcome.cs

@@ -0,0 +1,12 @@
+namespace Mr.BrickAdventures.Progression;
+
+/// <summary>
+/// How an Attempt finished, or that it has not finished yet. An Attempt reaches a terminal outcome
+/// once and refuses to change afterwards — that refusal is what guarantees one death costs one life.
+/// </summary>
+public enum AttemptOutcome
+{
+    InProgress,
+    Died,
+    Cleared,
+}