Fix narrow web layouts and loader branding

tests/simulation_history_ui_test.gd.uid

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+uid://djp7hoxcwgydv

tests/web_responsive_test.gd

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+extends SceneTree
+
+var failures := 0
+
+
+func _initialize() -> void:
+	call_deferred("_run")
+
+
+func _run() -> void:
+	var host := Control.new()
+	host.size = Vector2(240, 720)
+	root.add_child(host)
+	var selector = load("res://scripts/ui/study_selector.gd").new()
+	selector.size = host.size
+	host.add_child(selector)
+	await process_frame
+	selector._show_stage("step3")
+	selector._refresh_grid_columns()
+	await process_frame
+
+	_assert(selector.stage_scroll != null, "study selection should scroll vertically on short web viewports")
+	_assert(selector.stage_scroll.horizontal_scroll_mode == ScrollContainer.SCROLL_MODE_DISABLED, "study selection should never introduce horizontal scrolling")
+	_assert(selector.mode_grid.columns == 1, "phone-width mode cards should use one column")
+	_assert(selector.stage_content.get_combined_minimum_size().x <= host.size.x, "phone-width study content should fit inside the web canvas (minimum %.1f px)" % selector.stage_content.get_combined_minimum_size().x)
+	for card in selector.responsive_cards:
+		_assert(card.custom_minimum_size.x == 0.0, "phone-width cards should release their desktop minimum width")
+	for row in selector.responsive_card_rows:
+		_assert(row.vertical, "phone-width card content should stack instead of clipping")
+
+	var main_screen = load("res://scripts/ui/main.gd").new()
+	main_screen.size = host.size
+	host.add_child(main_screen)
+	await process_frame
+	main_screen._update_responsive_layout()
+	_assert(main_screen.theme_button.custom_minimum_size == Vector2(44, 44), "the theme toggle should keep a stable square footprint")
+	_assert(main_screen.theme_button.size.x >= 44.0 and main_screen.theme_button.size.y >= 44.0, "the theme toggle should not collapse into an oval")
+	_assert(not main_screen.user_label.visible and not main_screen.account_chevron_button.visible, "nonessential account controls should collapse on phone-width headers")
+
+	host.queue_free()
+	await process_frame
+	quit(1 if failures > 0 else 0)
+
+
+func _assert(condition: bool, message: String) -> void:
+	if condition:
+		return
+	failures += 1
+	push_error(message)

tests/web_responsive_test.gd.uid

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+uid://5j5vyo8jl6st