project.el integration

[edenworky]

I'm not enough of an emacs expert to know if this is PR-ready, but I here's my solution if anyone's interested:

(use-package vterm
  :ensure t
  :config
  (with-eval-after-load 'project
    (add-to-list 'project-switch-commands '(vterm-project "vterm" "t") t)
    (keymap-set project-prefix-map "t" #'vterm-project)))

(defun vterm-project ()
    (interactive)
    (defvar vterm-buffer-name)
    (let* ((default-directory (project-root (project-current t)))
           (vterm-buffer-name (project-prefixed-buffer-name "vterm"))
           (vterm-buffer (get-buffer vterm-buffer-name)))
      (if (and vterm-buffer (not current-prefix-arg))
          (pop-to-buffer vterm-buffer (bound-and-true-p display-comint-buffer-action))
        (vterm-other-window t))))

The vterm-project function is literally copied over from the project-eshell function with changed names.