[neovim] replace neo-tree with snacks.nvim

Replace neo-tree.nvim with snacks.nvim for file explorer functionality and
remove several other plugins including:
- mini-animate
- mini-starter
- indent-blankline

The snacks.nvim plugin provides better file explorer, dashboard, indentation
guides, and other UI improvements in a more cohesive package.

Also removed the large file autocommand as snacks.nvim handles this with its
bigfile module.

.config/nvim/lua/plugins/init.lua

@@ -1,17 +1,14 @@
+require("plugins.snacks")
 require("plugins.blink")
 require("plugins.copilot")
 require("plugins.avante")
 require("plugins.telescope")
-require("plugins.mini-animate")
 require("plugins.mini-comment")
 require("plugins.mini-pairs")
-require("plugins.mini-starter")
 require("plugins.mini-surround")
 require("plugins.treesitter")
 require("plugins.gitsigns")
-require("plugins.neo-tree")
 require("plugins.illuminate")
-require("plugins.indentline")
 require("plugins.lsp")
 require("plugins.go")
 require("plugins.typescript")