refactor: correctness fixes, API modernization, and cleanup

lua/pack.lua

@@ -32,7 +32,12 @@ end
 
 ---@param plugin ow.Pack.Plugin
 local function load(plugin)
-    local name = plugin.name:match("[^.]+"):lower()
+    local name = plugin.name:match("[^.]+")
+    if not name then
+        log.error("Invalid plugin name: %s", plugin.name)
+        return
+    end
+    name = name:lower()
     local path = string.format("%s/lua/plugins/%s.lua", config_dir, name)
 
     if vim.uv.fs_stat(path) then
@@ -121,7 +126,7 @@ end
 ---@type uv.uv_fs_event_t?
 local watcher = nil
 
----@type table<string, uv.uv_timer_t>
+---@type table<string, uv.uv_timer_t?>
 local timers = {}
 
 ---@class ow.Pack
@@ -183,18 +188,20 @@ function M.watch()
                 return
             end
 
-            if timers[filename] then
-                timers[filename]:stop()
+            local timer = timers[filename]
+            if timer ~= nil then
+                timer:stop()
             else
-                timers[filename] = vim.uv.new_timer()
+                timer = vim.uv.new_timer()
+                timers[filename] = timer
             end
 
-            timers[filename]:start(
+            timer:start(
                 100,
                 0,
                 vim.schedule_wrap(function()
-                    timers[filename]:stop()
-                    timers[filename]:close()
+                    timer:stop()
+                    timer:close()
                     timers[filename] = nil
 
                     local path = plugins_dir .. "/" .. filename