chore: clean up dotfiles and add gitignore whitelist

Switch to whitelist-based .gitignore to only track essential configs:
nvim, yazi, kitty, zsh, ideavim, karabiner, tmux, scripts, starship.
Remove history, compiled files, and plugin dirs from tracking.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

nvim/lua/plugins/nvim-tree.lua

@@ -34,6 +34,9 @@ return {
       highlight_git = true,
       highlight_opened_files = "all",
       icons = {
+        show = {
+          diagnostics = false,
+        },
         glyphs = {
           default = "",
           symlink = "",
@@ -61,12 +64,6 @@ return {
     diagnostics = {
       enable = true,
       show_on_dirs = true,
-      icons = {
-        hint = "",
-        info = "",
-        warning = "",
-        error = "",
-      },
     },
     filters = {
       dotfiles = false,