NEO-122: Fix economy HUD positioning so panel renders on screen.

Bottom anchors placed the section off-screen before layout; use explicit
position/size from viewport height and draw above HudRoot via z_index.

client/scenes/main.tscn

@@ -1304,16 +1304,11 @@ autowrap_mode = 3
 text = "Cooldowns: —"
 
 [node name="EconomyHudSection" type="VBoxContainer" parent="UICanvas" unique_id=9000014]
-layout_mode = 1
+z_index = 10
-anchors_preset = 3
-anchor_top = 1.0
-anchor_bottom = 1.0
 offset_left = 8.0
-offset_top = -440.0
+offset_top = 400.0
 offset_right = 664.0
-offset_bottom = -8.0
+offset_bottom = 800.0
-grow_horizontal = 2
-grow_vertical = 0
 script = ExtResource("20_economy_hud")
 
 [node name="HeaderRow" type="HBoxContainer" parent="UICanvas/EconomyHudSection" unique_id=9000015]

client/scripts/prototype_economy_hud_section.gd

@@ -15,11 +15,14 @@ const PANEL_WIDTH := 656.0
 
 
 func _ready() -> void:
+	z_index = 10
 	_toggle.button_pressed = true
 	_body_scroll.visible = true
 	_toggle.toggled.connect(_on_toggle_toggled)
 	get_viewport().size_changed.connect(_apply_viewport_layout)
 	call_deferred("_apply_viewport_layout")
+	await get_tree().process_frame
+	_apply_viewport_layout()
 
 
 func _on_toggle_toggled(pressed: bool) -> void:
@@ -46,19 +49,19 @@ func scroll_body_to_recipes() -> void:
 func _apply_viewport_layout() -> void:
 	if not is_instance_valid(_body_scroll):
 		return
-	var vp_height: float = get_viewport().get_visible_rect().size.y
+	var vp_size: Vector2 = get_viewport().get_visible_rect().size
+	if vp_size.y <= 1.0:
+		return
 	var header_height: float = _measure_header_height()
 	var body_height: float = max(
-		MIN_BODY_SCROLL_HEIGHT, vp_height * MAX_VIEWPORT_HEIGHT_FRACTION - header_height
+		MIN_BODY_SCROLL_HEIGHT, vp_size.y * MAX_VIEWPORT_HEIGHT_FRACTION - header_height
 	)
 	_body_scroll.custom_minimum_size = Vector2(PANEL_WIDTH, body_height)
 	var panel_height: float = header_height
 	if _body_scroll.visible:
 		panel_height += body_height
-	offset_left = SIDE_MARGIN
+	position = Vector2(SIDE_MARGIN, vp_size.y - panel_height - BOTTOM_MARGIN)
-	offset_right = SIDE_MARGIN + PANEL_WIDTH
+	size = Vector2(PANEL_WIDTH, panel_height)
-	offset_bottom = -BOTTOM_MARGIN
-	offset_top = -panel_height - BOTTOM_MARGIN
 
 
 func _measure_header_height() -> float:

client/test/prototype_economy_hud_section_test.gd

@@ -62,3 +62,19 @@ func test_toggle_expands_body_again() -> void:
 	await await_idle_frame()
 	# Assert
 	assert_bool(section.call("is_body_visible")).is_true()
+
+
+func test_viewport_layout_pins_section_above_bottom_margin() -> void:
+	# Arrange
+	var section: Control = _build_section() as Control
+	add_child(section)
+	await await_idle_frame()
+	await get_tree().process_frame
+	# Act
+	section.call("_apply_viewport_layout")
+	await get_tree().process_frame
+	# Assert
+	var vp_height: float = get_viewport().get_visible_rect().size.y
+	assert_that(section.position.y).is_greater(vp_height * 0.2)
+	assert_that(section.position.y + section.size.y).is_less_equal(vp_height)
+