Exit copy mode on normal key press and fix README

Normal letter keys (a-z etc.) now exit copy mode and forward the
key to the terminal, so the user can seamlessly resume typing.

Also fix README:
- Copy mode keybinding was C-c C-k, actual binding is C-c C-t
- Add missing keys to copy mode table: C-n/C-p, M-v/C-v, M-</M->
  C-e, and document the new exit-on-keypress behavior

Author: dakra

README.md

@@ -82,7 +82,7 @@ test "$INSIDE_EMACS" = 'ghostel'; and source "$EMACS_GHOSTEL_PATH/etc/ghostel.fi
 | `C-c C-z`   | Send suspend (C-z)                     |
 | `C-c C-d`   | Send EOF (C-d)                         |
 | `C-c C-\`   | Send quit (C-\)                        |
-| `C-c C-k`   | Enter copy mode                        |
+| `C-c C-t`   | Enter copy mode                        |
 | `C-y`       | Yank from kill ring (bracketed paste)  |
 | `M-y`       | Yank-pop (cycle through kill ring)     |
 | `C-c C-y`   | Paste from kill ring                   |
@@ -97,15 +97,20 @@ Keys listed in `ghostel-keymap-exceptions` (default: `C-c`, `C-x`, `C-u`,
 
 ### Copy mode
 
-Enter with `C-c C-k`. Standard Emacs navigation works.
-
-| Key           | Action                  |
-|---------------|-------------------------|
-| `C-SPC`       | Set mark                |
-| `M-w` / `C-w` | Copy selection and exit |
-| `C-c C-n`     | Jump to next prompt     |
-| `C-c C-p`     | Jump to previous prompt |
-| `q`           | Exit without copying    |
+Enter with `C-c C-t`. Standard Emacs navigation works.
+Normal letter keys exit copy mode and send the key to the terminal.
+
+| Key           | Action                          |
+|---------------|---------------------------------|
+| `C-SPC`       | Set mark                        |
+| `M-w` / `C-w` | Copy selection and exit         |
+| `C-n` / `C-p` | Move line (scrolls at edges)    |
+| `M-v` / `C-v` | Scroll page up / down           |
+| `M-<` / `M->` | Jump to top / bottom of buffer  |
+| `C-c C-n`     | Jump to next prompt             |
+| `C-c C-p`     | Jump to previous prompt         |
+| `C-t`         | Exit without copying            |
+| `a`–`z`       | Exit and send key to terminal   |
 
 Soft-wrapped newlines are automatically stripped from copied text.
 

ghostel.el

@@ -1011,7 +1011,8 @@ pasted using bracketed paste."
 
 (defvar ghostel-copy-mode-map
   (let ((map (make-sparse-keymap)))
-    (define-key map (kbd "q") #'ghostel-copy-mode-exit)
+    ;; Normal letter keys exit copy mode and send the key to the terminal
+    (define-key map [remap self-insert-command] #'ghostel-copy-mode-exit-and-send)
     (define-key map (kbd "C-c C-t") #'ghostel-copy-mode-exit)
     (define-key map (kbd "M-w") #'ghostel-copy-mode-copy)
     (define-key map (kbd "C-w") #'ghostel-copy-mode-copy)
@@ -1072,6 +1073,13 @@ Press \\`q' or \\[ghostel-copy-mode-exit] to exit without copying."
     (ghostel--invalidate)
     (message "Copy mode exited")))
 
+(defun ghostel-copy-mode-exit-and-send ()
+  "Exit copy mode and send the key that triggered exit to the terminal."
+  (interactive)
+  (ghostel-copy-mode-exit)
+  (when ghostel--term
+    (ghostel--self-insert)))
+
 (defun ghostel--filter-soft-wraps (text)
   "Remove newlines from TEXT that were inserted by soft line wrapping.
 These are newlines with the `ghostel-wrap' text property."