feat(ui): added update checker

lua/lazy/manage/checker.lua

@@ -0,0 +1,51 @@
+local Config = require("lazy.core.config")
+local Manage = require("lazy.manage")
+local Util = require("lazy.util")
+local Git = require("lazy.manage.git")
+
+local M = {}
+
+M.running = false
+M.updated = {}
+
+function M.start()
+  M.fast_check()
+  M.check()
+end
+
+function M.fast_check()
+  for _, plugin in pairs(Config.plugins) do
+    local info = Git.info(plugin.dir)
+    local target = Git.get_target(plugin)
+    if info and target and info.commit ~= target.commit then
+      plugin._.has_updates = true
+    end
+  end
+  M.report()
+end
+
+function M.check()
+  Manage.check({
+    show = false,
+    concurrency = Config.options.checker.concurrency,
+  }):wait(function()
+    M.report()
+    vim.defer_fn(M.check, Config.options.checker.frequency * 1000)
+  end)
+end
+
+function M.report()
+  local lines = {}
+  for _, plugin in pairs(Config.plugins) do
+    if plugin._.has_updates and not vim.tbl_contains(M.updated, plugin.name) then
+      table.insert(lines, "- **" .. plugin.name .. "**")
+      table.insert(M.updated, plugin.name)
+    end
+  end
+  if #lines > 0 and Config.options.checker.notify then
+    table.insert(lines, 1, "# Plugin Updates")
+    Util.info(lines)
+  end
+end
+
+return M