feat(plugin): simplify plugin specs and update keybindings

Simplify plugin configurations and improve keybinding consistency.

New Features
- Use plain plugin names instead of version‑locked specifications.

Enhancements
- Change colorcolumn setting from number to string.
- Replace multiple update mappings with a single vim.pack.update() call.

Bug Fixes
- Remove outdated plugin manager mappings that caused duplicate actions.

plugin/completion.lua

@@ -1,6 +1,6 @@
 add({
 	"saghen/blink.lib",
-	{ src = "saghen/blink.cmp", version = "v0.*" },
+	"saghen/blink.cmp",
 	"L3MON4D3/LuaSnip",
 	"rafamadriz/friendly-snippets",
 })