refactor: implement modular plugin structure

lua/custom/plugins/health.lua

@@ -0,0 +1,29 @@
+--[plugins/health.lua]
+
+return {
+    {
+        "nvim-lua/plenary.nvim",
+        config = function()
+        local health = vim.health or require("health")
+        health.start("System Checks")
+
+        -- Check Neovim version
+        local version = vim.version()
+        if version and version.major >= 0 and version.minor >= 9 then
+            health.ok("Neovim version is sufficient: " .. version.major .. "." .. version.minor)
+            else
+                health.error("Neovim 0.9+ required, found " .. version.major .. "." .. version.minor)
+                end
+
+                -- Check executables
+                local executables = { "git", "make", "unzip", "rg" }
+                for _, exe in ipairs(executables) do
+                    if vim.fn.executable(exe) == 1 then
+                        health.ok(exe .. " is installed")
+                        else
+                            health.warn(exe .. " not found in PATH")
+                            end
+                            end
+                            end,
+    },
+}