feat(progression): capabilities the adapters need (commit A of the swap)

no behaviour change - additive only.

GrantSkill: pickups are free unlocks, and collecting one already owned is
a no-op rather than a free upgrade.
RevokeSkill: for skills that consume themselves (brick shield).
AbandonAttempt: leaving a level without dying, so no life is charged.

ApplyCheat rewrites the Playthrough through its snapshot rather than via
SetLives/AddCoins mutators, which ADR-0005 rules out - a bare mutator is
an invitation, and the old code had two paths to exactly that. Every
value is re-validated on the way back in and a rejected cheat leaves the
Playthrough untouched, which is asserted.

73 tests.

Autoloads/ProgressionRoot.cs

@@ -174,6 +174,37 @@ public partial class ProgressionRoot : Node
         return outcome;
     }
 
+    /// <summary>Free unlock, as a pickup gives. Returns false if it was already owned.</summary>
+    public bool GrantSkill(SkillId skill)
+    {
+        if (_service == null) return false;
+
+        var granted = _service.GrantSkill(skill);
+        Publish();
+        return granted;
+    }
+
+    /// <summary>Takes a Skill away — for Skills that consume themselves.</summary>
+    public bool RevokeSkill(SkillId skill)
+    {
+        if (_service == null) return false;
+
+        var revoked = _service.RevokeSkill(skill);
+        Publish();
+        return revoked;
+    }
+
+    /// <summary>Discards the current Attempt without charging a life — leaving a Level, not dying.</summary>
+    public void AbandonAttempt() => Run(() => _service.AbandonAttempt());
+
+    /// <summary>Console only — see <see cref="ProgressionService.ApplyCheat"/>.</summary>
+    public void ApplyCheat(Func<PlaythroughSnapshot, PlaythroughSnapshot> change) =>
+        Run(() => _service.ApplyCheat(change));
+
+    /// <summary>Whether there is a resumable Playthrough, for enabling the Continue button.</summary>
+    public bool HasSavedPlaythrough =>
+        PeekPlaythrough(SoleSlot) == LoadOutcome.Loaded;
+
     private void Run(System.Action operation)
     {
         if (_service == null) return;