refactor: migrate to template-based theme system, clean up old per-theme configs

- Remove per-theme app configs (alacritty, foot, ghostty, hyprland,
  hyprlock, mako, rofi, swayosd, tmux, walker, waybar, etc.) now
  handled by default/themed/ templates
- Update omarchy scripts (bg-next, list, set) for new template flow
- Update configs: bootstrap, nvim, rofi, tmux, mako
- Tweak installers (02-install-base.sh, btop, desktop, goose, nvim,
  obsidian, theme, tmux)
- Remove obsolete hyprland-rofi-* and hyprland-walker-* scripts
- Update neovim.lua across remaining themes

themes/osaka-jade/neovim.lua

@@ -1,9 +1,12 @@
 return {
-	"ribru17/bamboo.nvim",
-	lazy = false,
-	priority = 1000,
-	config = function()
-		require("bamboo").setup({})
-		require("bamboo").load()
-	end,
+  {
+    "ribru17/bamboo.nvim",
+    priority = 1000,
+  },
+  {
+    "LazyVim/LazyVim",
+    opts = {
+      colorscheme = "bamboo",
+    },
+  },
 }