Integrate Darwin branch features into integration branch

- Add AeroSpace window manager configuration and file setup
- Add LazyVim setup with gh-addressed plugin
- Add Darwin-specific secrets (work key + work-wg.age)
- Reorganize kitty config into separate profile
- Make Linux-only packages conditional (iputils, strace, vim-tidal)
- Fix nix-darwin compatibility (remove deprecated options, add primaryUser)
- Update font packages to new nerd-fonts structure
- Add platform-aware nrb alias (detects Darwin vs Linux)
- Use shared tmux config instead of Darwin-specific duplicate
- Update Darwin host config (disable yabai, enable AeroSpace)
- Fix sketchybar permissions and gitignore .direnv tracking

Integration branch now works on both Darwin and Linux with all Darwin improvements.

Amp-Thread-ID: https://ampcode.com/threads/T-9427454f-2ecb-40ef-998b-0f33f0950105
Co-authored-by: Amp <amp@ampcode.com>

home/profiles/kitty/default.nix

@@ -0,0 +1,11 @@
+{ pkgs, config, lib, ... }:
+
+{
+  home.packages = with pkgs; [
+    kitty
+  ];
+  home.file = {
+    ".config/kitty/kitty.conf".source = ./kitty.conf;
+    ".config/kitty/ayu.conf".source = ./ayu-kitty.conf;
+  };
+}