Save The Tree implementation and acceptance work in progress

Preserve production code, regression fixtures, audio assets and provenance, test infrastructure, and the original-completion plan and progress ledger. Final game and Windows acceptance remain pending; excluded local artifacts and native experiments are not part of this snapshot.

tests/ui/capture_pixel_tower.gd

@@ -26,6 +26,8 @@ func _run() -> void:
 	var state: Variant = root.get_node("GameState")
 	_clock.reset(1, 6, 0)
 	state.reset()
+	# Disposable Demo fixture funds exact Doran signing_cost 300; DEFAULT5000 and paid hire stay unchanged.
+	state.resources[&"gold"] += 300
 	var initialized: Dictionary = _runtime.initialize(_clock, state, 424242)
 	_clock.set_paused(true)
 	_runtime.configure_save_policy({&"enabled": false, &"daily_checkpoint_enabled": false})