feat(emacs): Eshell stuff

- Fancify prompt
  - Shows success of last command.
  - TRAMP prefix is made distinct.
  - CWD is abbreviated.
- cd to project root (`cdp`).
- Imitate using `C-d` / send-EOF to exit.
- Opening popup shell puts user in insert state.
- Fixes TRAMP customisation.

Nicely done! }:3

users/crumb/programs/emacs/modules/syd-tramp.el

@@ -1,10 +1,9 @@
 ;;; syd-tramp.el -*- lexical-binding: t; -*-
 
-(use-package tramp
-  :defer t
-  :custom ((tramp-persistency-file-name (file-name-concat syd-cache-dir
-                                                          "tramp"))
-           (tramp-auto-save-directory
-            (file-name-concat syd-cache-dir "tramp-autosave/"))))
+(with-eval-after-load 'tramp
+  (setq tramp-persistency-file-name
+        (file-name-concat syd-cache-dir "tramp"))
+  (setq tramp-auto-save-directory
+        (file-name-concat syd-cache-dir "tramp-autosave/")))
 
 (provide 'syd-tramp)