Add Emacs config with install scripts for laptop and work

Shared: init.el / early-init.el with Vertico stack, Corfu, Eglot,
treesit-auto, Catppuccin Mocha, doom-modeline, Magit, avy, harpoon,
embark, wgrep, expand-region, envrc, org-mode, and drop-in lang loader.

Lang configs split by stow target:
- shared: elisp, org
- laptop: C/C++, Rust, Go, LaTeX (AUCTeX + latexmk + Zathura)
- work:   C#, JS/TS/HTML/CSS/React (apheleia+prettier), Copilot

install-personal.sh: Fedora — gcc/clang, rustup, Go, texlive, zathura
install-work.sh: Ubuntu 24.04 WSL — dotnet-sdk-10.0, Node 22 via nvm, ts-ls

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

work/.config/emacs/lisp/langs/copilot.el

@@ -0,0 +1,16 @@
+;;; lisp/langs/copilot.el --- GitHub Copilot  -*- lexical-binding: t -*-
+
+;; copilot.el is not on MELPA; installed via package-vc (Emacs 29+)
+(use-package copilot
+  :vc (:url "https://github.com/copilot-emacs/copilot.el" :rev :newest)
+  :hook (prog-mode . copilot-mode)
+  :bind (:map copilot-completion-map
+              ;; copilot-completion-map is only active when ghost text is showing,
+              ;; so these bindings don't interfere with Corfu's popup
+              ("<tab>" . copilot-accept-completion)
+              ("TAB"   . copilot-accept-completion)
+              ("M-f"   . copilot-accept-completion-by-word)
+              ("M-n"   . copilot-next-completion)
+              ("M-p"   . copilot-previous-completion))
+  :custom
+  (copilot-idle-delay 0.5))