port: make ScreenView say what it could not draw; refute 'first-declared paints first'

skipped[] has been tracked and read by nobody since P1, under a comment saying a
silently missing element looks like art. _note_structural prints from inside
ScreenView rather than returning a value for a caller -- routing it through a
caller is exactly what did not happen. Structural skips only; transparent-at-
rest is ordinary animation. Zero found today: a guard, not a fix.

The first version of that scan was a FALSE PASS: screen_view.gd did not parse
(a line inserted at three tabs inside a four-tab block -- the substring assert
matched a shallower indent), so grep counted zero from a dead script. The scan
now counts the summary line as a positive control.

Refutes 'the first-declared element paints first', which would have made the
forced-backdrop rule redundant since all six forced elements are index 0. False
on 8 of 16 screens -- decisively on main_menu, where index 0 is pteff00, painted
LAST, and pteff00 is a measured control.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N7FiFFFwbvG2uxdcEh8HyF

port/scripts/boot.gd

@@ -233,6 +233,7 @@ func _ready() -> void:
 	if _menu != null and _sequence.is_empty():
 		_menu_enter(name, true)
 
+	view.structural_skips.clear()
 	var settle := view.settle_time()
 	print("screen %s: %d elements, %d in paint order, design %dx%d, settles at t=%d (%.3f s)" % [
 		name, view.screen["elements"].size(), view.screen["paint_order"].size(),

port/scripts/screen_view.gd

@@ -101,6 +101,19 @@ var tree: ExportTree = null
 var screen: Dictionary = {}
 var textures: Dictionary = {}
 var skipped: Array[String] = []
+
+## Structural skips accumulated over the life of the CURRENT screen, deduplicated.
+##
+## 🔴 `skipped` itself is per-frame and was read by NOBODY. Its own comment says
+## "a silently missing element looks like art" -- and for eight milestones
+## nothing printed it, so the port could drop an element every frame and say so
+## to no one. That is the same shape as the black hold, which was implemented,
+## called, and emitted nothing until somebody filmed it.
+##
+## Only STRUCTURAL skips accumulate here. "(transparent at rest)" is ordinary
+## animation -- every element is transparent at some instant -- and reporting it
+## would bury the three that mean something under the one that never does.
+var structural_skips: Array[String] = []
 var drawn: Array[String] = []
 
 ## Which button is highlighted, by element id. P1 leaves it empty: initial focus
@@ -604,6 +617,7 @@ func _draw() -> void:
 			var tex: Texture2D = textures.get(rel)
 			if tex == null:
 				skipped.append("%s (sprite failed to load)" % id)
+				_note_structural("%s (sprite failed to load)" % id)
 				continue
 			_draw_quad(tex, placement(pose, pivot, tex.get_size()), colour, pivot, pos, rot)
 			drawn.append(id)
@@ -616,3 +630,17 @@ func _draw() -> void:
 			# A .t32 element whose sprite the exporter could not produce. Saying
 			# so is the point -- a silently missing element looks like art.
 			skipped.append("%s (no sprite in the export)" % id)
+			_note_structural("%s (no sprite in the export)" % id)
+
+
+## Record a skip that is NOT ordinary animation, and SAY SO, once per screen.
+##
+## It prints from here rather than returning a value for a caller to report,
+## because "the caller will report it" is precisely what did not happen: the
+## per-frame `skipped` list has been correct and unread since P1. A fact that
+## needs somebody else to remember to look at it is a fact that goes unnoticed.
+func _note_structural(what: String) -> void:
+	if not structural_skips.has(what):
+		structural_skips.append(what)
+		push_warning("element not drawn: %s" % what)
+		print("  🔴 element NOT DRAWN: %s" % what)