Split laptop/work into independent stow packages with shared/ base

- Remove work/laptop detection logic from nvim and emacs configs; each
  package now has a self-contained init that requires no runtime checks
- Create shared/ stow package containing nvim/init.lua, emacs/init.el,
  common-dev-settings.el, org-bindings.el, tmux, ghostty, and ranger
- Rename laptop-languages.lua / work-languages.lua → languages.lua in
  each package; shared/init.lua uses require('languages') generically
- Rename work-dev-settings.el → dev-settings.el to match laptop naming
- Expand work/ to include the full set of dev tools (tmux, ghostty,
  ranger, emacs, neovim) without email/calendar tooling
- Add Makefile with `make laptop` and `make work` targets (each runs
  a single `stow shared <profile>` invocation)

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

work/.config/nvim/lua/languages.lua

@@ -1,5 +1,7 @@
--- Loaded by init.lua when this file exists (work stow package active).
--- Mirrors work-dev-settings.el: C#, TypeScript, JavaScript, CSS, HTML + Prettier.
+-- Work language pack: C#, TypeScript, JavaScript, CSS, HTML, Prettier.
+-- Loaded by shared/init.lua via require('languages').
+
+
 return {
   servers = {
     ts_ls     = {},  -- handles TypeScript, TSX, JavaScript, JSX