Type vlayer forward declarations and config entries

The gui element locals are declared at the top and assigned far below,
so emmylua inferred them as nil at every use site.

circuit_oc was reassigned from a control behaviour to a logistic
section, which hid every section method behind the wrong type.

allowed_items entries carry heterogeneous optional properties, now
described by a class.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

exp_legacy/module/config/vlayer.lua

@@ -35,6 +35,20 @@ return {
         storage_output = 1, -- >0 allows for item teleportation (allowed_items only)
     },
 
+    --- @class Vlayer.ItemProperties
+    --- @field starting_value number
+    --- @field required_area number
+    --- @field production number?
+    --- @field discharge number?
+    --- @field capacity number?
+    --- @field surface_area number?
+    --- @field fuel_value number?
+    --- @field power boolean?
+    --- @field modded boolean? Set when the item is registered from a modded equivalent
+    --- @field base_game_equivalent string?
+    --- @field multiplier number?
+
+    --- @type table<string, Vlayer.ItemProperties>
     allowed_items = { --- @setting allowed_items List of all items allowed in vlayer storage and their properties
         --[[
             Allowed properties:

exp_legacy/module/modules/control/vlayer.lua

@@ -14,10 +14,10 @@ local mega = 1000000
 local vlayer = {}
 local vlayer_data = {
     entity_interfaces = {
-        energy = {},
-        circuit = {},
-        storage_input = {},
-        storage_output = {},
+        energy = {}, --- @type LuaEntity[]
+        circuit = {}, --- @type LuaEntity[]
+        storage_input = {}, --- @type LuaEntity[]
+        storage_output = {}, --- @type LuaEntity[]
     },
     properties = {
         total_surface_area = 0,
@@ -582,11 +582,11 @@ local function handle_circuit_interfaces()
         if not interface.valid then
             vlayer_data.entity_interfaces.circuit[index] = nil
         else
-            local circuit_oc = interface.get_or_create_control_behavior()
-            if circuit_oc.sections_count == 0 then
-                circuit_oc.add_section()
+            local control = interface.get_or_create_control_behavior()
+            if control.sections_count == 0 then
+                control.add_section()
             end
-            circuit_oc = circuit_oc.sections[1]
+            local circuit_oc = control.sections[1]
             local signal_index = 1
             local circuit = vlayer.get_circuits()
 

exp_legacy/module/modules/gui/vlayer.lua

@@ -22,9 +22,9 @@ local function aabb_align_expand(aabb)
     }
 end
 
-local vlayer_container
-local vlayer_gui_control_type
-local vlayer_gui_control_list
+local vlayer_container --- @type ExpElement
+local vlayer_gui_control_type --- @type ExpElement
+local vlayer_gui_control_list --- @type ExpElement
 
 local vlayer_control_type_list = {
     [1] = "energy",
@@ -87,7 +87,7 @@ SelectArea:on_selection(function(event)
     local container = Gui.get_left_element(vlayer_container, player)
     local disp = container.frame["vlayer_st_2"].disp.table
     local target = vlayer_control_type_list[disp[vlayer_gui_control_type.name].selected_index]
-    local entities
+    local entities --- @type LuaEntity[]
 
     if config.power_on_space and event.surface and event.surface.platform and target == "energy" then
         if player.force.technologies[config.power_on_space_research.name].level >= config.power_on_space_research.level then