move clean() to the fs file

lua/dep/fs.lua

@@ -19,4 +19,45 @@ function fs:link(package, cb)
   end)
 end
 
+--- clean out old packages
+---@param package package any package
+function fs:clean(package)
+  h.uv.fs_scandir(
+    package.get_base_dir(),
+    vim.schedule_wrap(function(err, handle)
+      if err then
+        logger:log("error", "failed to clean; reason: %s", err)
+      else
+        local queue = {}
+
+        while handle do
+          local name = h.uv.fs_scandir_next(handle)
+          if name then
+            queue[name] = package.get_base_dir().."/"..name
+          else
+            break
+          end
+        end
+
+        -- keep packages that still exist
+        for _, pkg in pairs(package.get_packages()) do
+          queue[pkg.name] = nil
+        end
+
+        for name, dir in pairs(queue) do
+          local co = coroutine.create(function()
+            local ok = vim.fn.delete(dir, "rf")
+            if ok then
+              logger:log("clean", "deleted %s", name)
+            else
+              logger:log("error", "failed to delete %s", name)
+            end
+          end)
+          coroutine.resume(co)
+        end
+      end
+    end)
+  )
+end
+
 return fs