Add client dropper registration and merging functionality

inventoryManager.lua

@@ -648,6 +648,9 @@ local cache = {
     droppers      = {},   -- list of available dropper peripherals for dispensing
 }
 
+-- Client-registered droppers, keyed by clientId
+local clientDroppers = {}
+
 -------------------------------------------------
 -- Activity state (shown on monitor)
 -------------------------------------------------
@@ -918,6 +921,19 @@ local function refreshCache(onProgress)
         if a.isDefault ~= b.isDefault then return a.isDefault end
         return a.name < b.name
     end)
+
+    -- Merge in droppers registered by remote clients
+    local seenNames = {}
+    for _, d in ipairs(droppers) do seenNames[d.name] = true end
+    for clientId, clientList in pairs(clientDroppers) do
+        for _, d in ipairs(clientList) do
+            if not seenNames[d.name] then
+                table.insert(droppers, { name = d.name, isDefault = false, clientId = clientId })
+                seenNames[d.name] = true
+            end
+        end
+    end
+
     cache.droppers = droppers
 
     -- Furnace count already computed from single-pass above
@@ -943,6 +959,7 @@ local function refreshCache(onProgress)
             barrelOk   = cache.barrelOk,
             furnaceCount = cache.furnaceCount,
             furnaceStatus = cache.furnaceStatus,
+            droppers   = cache.droppers,
             savedAt    = os.epoch("utc"),
         }
         local f = fs.open(CACHE_FILE, "w")
@@ -972,6 +989,7 @@ local function loadCacheFromDisk()
             cache.barrelOk     = data.barrelOk     or false
             cache.furnaceCount = data.furnaceCount or 0
             cache.furnaceStatus = data.furnaceStatus or {}
+            cache.droppers     = data.droppers     or {}
         else
             error("invalid cache data")
         end
@@ -3353,6 +3371,32 @@ local function main()
                         print("[NET] Sort barrel: " .. message.barrelName)
                         pcall(sortBarrel, message.barrelName)
                         pcall(broadcastState)
+                    elseif message.type == "register_droppers" and message.clientId and message.droppers then
+                        -- Client is announcing its locally-attached droppers
+                        local cid = tostring(message.clientId)
+                        clientDroppers[cid] = message.droppers
+                        print(string.format("[NET] Client %s registered %d dropper(s)", cid, #message.droppers))
+                        -- Rebuild the merged dropper list immediately
+                        local seenNames = {}
+                        local merged = {}
+                        -- Master droppers first
+                        for _, d in ipairs(cache.droppers or {}) do
+                            if not d.clientId then
+                                table.insert(merged, d)
+                                seenNames[d.name] = true
+                            end
+                        end
+                        -- Then all client droppers
+                        for clientId, clientList in pairs(clientDroppers) do
+                            for _, d in ipairs(clientList) do
+                                if not seenNames[d.name] then
+                                    table.insert(merged, { name = d.name, isDefault = false, clientId = clientId })
+                                    seenNames[d.name] = true
+                                end
+                            end
+                        end
+                        cache.droppers = merged
+                        pcall(broadcastState)
                     elseif message.type == "craft" and message.recipeIdx then
                         print(string.format("[NET] Craft request: recipe #%d", message.recipeIdx))
                         local pok, ok, err = pcall(craftItem, message.recipeIdx)