Added environment panel for depth, pressure and outside temperature.

scenes/environment_demo.tscn

@@ -0,0 +1,52 @@
+[gd_scene format=3]
+
+[ext_resource type="Script" path="res://scripts/environment_demo.gd" id="1"]
+[ext_resource type="PackedScene" path="res://components/environment_panel.tscn" id="2"]
+
+[node name="EnvironmentDemo" type="VBoxContainer"]
+offset_left = 24.0
+offset_top = 24.0
+offset_right = 624.0
+offset_bottom = 420.0
+theme_override_constants/separation = 16
+script = ExtResource("1")
+
+[node name="Notice" type="Label" parent="."]
+layout_mode = 2
+text = "SIMULATED / ENVIRONMENT INSTRUMENT"
+
+[node name="EnvironmentPanel" parent="." instance=ExtResource("2")]
+layout_mode = 2
+size_flags_horizontal = 4
+
+[node name="Controls" type="HBoxContainer" parent="."]
+layout_mode = 2
+
+[node name="State" type="OptionButton" parent="Controls"]
+layout_mode = 2
+selected = 1
+item_count = 8
+popup/item_0/text = "Surface / zero"
+popup/item_0/id = 0
+popup/item_1/text = "Shallow operation"
+popup/item_1/id = 1
+popup/item_2/text = "Operating depth"
+popup/item_2/id = 2
+popup/item_3/text = "Near depth limit"
+popup/item_3/id = 3
+popup/item_4/text = "Pressure near limit"
+popup/item_4/id = 4
+popup/item_5/text = "Over limits"
+popup/item_5/id = 5
+popup/item_6/text = "Stop feed / stale"
+popup/item_6/id = 6
+popup/item_7/text = "No telemetry"
+popup/item_7/id = 7
+
+[node name="Contrast" type="CheckButton" parent="Controls"]
+layout_mode = 2
+text = "High contrast"
+
+[node name="Note" type="Label" parent="."]
+layout_mode = 2
+text = "Zero-inclusive log scale · shallow depths expanded"