Shift-Esc always backs out: in every mode and pane it goes to the previous pane, as Esc does from normal, and a raw program never sees it; Ctrl-b alone toggles raw

Shift-Esc switched a terminal in normal or insert mode into raw, so the
one key meant to get out of anything got a script or a person into a
program instead. It is now handled before any mode: an open prompt is
closed, insert mode left, a pending count dropped, and Last runs, the
pane keeping its mode (a raw terminal stays raw). Ctrl-b is the only
switch between raw and normal. The keymap's two chords become one,
back_out; the cheatsheet row, the guide's mode table and the tutor say
so, and the tty and builtins goldens are re-recorded.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

3 files changed, 20 insertions, 26 deletions

diff --git a/test/snapshots/builtins.golden b/test/snapshots/builtins.golden
index 27b43a3a..68fab516 100644
--- a/test/snapshots/builtins.golden
+++ b/test/snapshots/builtins.golden
@@ -73,9 +73,9 @@
 |58:     43  Esc and Shift-Esc, by mode:
 |59:     44
 |60:     45    NORMAL   Esc       back to the previous pane (`Last`, SPC j j)
-|61:     46             Shift-Esc the same; in a terminal it switches to RAW
+|61:     46             Shift-Esc the same
 |62:     47    INSERT   Esc       back to NORMAL
-|63:     48             Shift-Esc the same; in a terminal it switches to RAW
+|63:     48             Shift-Esc out of INSERT and back to the previous pane
 |64:     49    RAW      Esc       goes to the program, except at an idle,
 |65:     50                       EMPTY shell prompt: back to the previous pane
 |66:     51             Shift-Esc always back to the previous pane
diff --git a/test/snapshots/tty.golden b/test/snapshots/tty.golden
index 981a5c7f..b1ee7afd 100644
--- a/test/snapshots/tty.golden
+++ b/test/snapshots/tty.golden
@@ -29,15 +29,14 @@
 |4:   ls                                                ls
 |6:   echo SNAP''OK
 |8:
-== snap shift-esc-on grid=100x31 cursor=4,8
-|2: $  /tmp/pardes-snap/tty/cwd Tty+bash Save Mode Fil   /tmp/pardes-snap/tty/cwd Tty+bash Save Mode Fil
-|4:   $ ls                                              ls
-|6:   $ echo SNAP''OK
-|8:   $
-== snap shift-esc-nodoc grid=100x31 cursor=4,21
-|4:   $ ls                                       Last   ls
-== snap ctrl-b-off grid=100x31 cursor=4,21
-|4:   $ ls                                              ls
+== snap shift-esc-normal grid=100x31 cursor=4,21
+|4:   ls                                         Last   ls
+== snap ctrl-b-on grid=100x31 cursor=4,21
+|4:   ls                                                ls
 |17: $  /tmp/pardes-snap/tty/cwd Tty+bash Save Mode Fil
 |19:   $ ls
 |21:   $
+== snap ctrl-b-off grid=100x31 cursor=4,21
+|17:    /tmp/pardes-snap/tty/cwd Tty+bash Save Mode Fil
+|19:   ls
+|21:
diff --git a/test/snapshots/tty.snap b/test/snapshots/tty.snap
index 6ce0d5ba..48fffbd1 100644
--- a/test/snapshots/tty.snap
+++ b/test/snapshots/tty.snap
@@ -1,11 +1,8 @@
-# tty mode round-trip: Ctrl-b in, run a command, Ctrl-b out. Shift-Esc (CSI
-# 27;2u — needs a host that reports modifiers on Escape) also gets you IN; a
-# PLAIN Esc does not, it still goes to the shell.
-#
-# Getting OUT is Ctrl-b alone. Shift-Esc in tty is what Escape is in normal
-# mode instead — Last, the pane you were in before this one — leaving this pane
-# in tty so coming back lands in the program you left. The hop itself is
-# covered by a unit test in pardes.zig.
+# tty mode round-trip: Ctrl-b in, run a command, Ctrl-b out. Ctrl-b is the one
+# switch between raw and normal. Shift-Esc (CSI 27;2u — needs a host that
+# reports modifiers on Escape) never switches: in every mode it is what Escape
+# is in normal mode — Last, the pane you were in before this one — and a raw
+# terminal stays raw. The hop itself is covered by a unit test in pardes.zig.
 file m.txt marker
 start 31 100 -n 3
 wait 8000 m.txt
@@ -21,16 +18,14 @@ snap tty-echo
 key c-b
 stable 600 8000
 snap tty-off
-# Shift-Esc: in, the same as Ctrl-b...
+# Shift-Esc from normal: never into raw; it backs out to the previous pane.
 send \e[27;2u
 stable 600 8000
-snap shift-esc-on
-# ...but not out. With no doc pane to hop to it changes nothing: still tty,
-# prompts still shown, same pane focused.
-send \e[27;2u
+snap shift-esc-normal
+# Ctrl-b is the switch: into raw, and out again.
+key c-b
 stable 600 8000
-snap shift-esc-nodoc
-# Ctrl-b still leaves tty in place, which is now the only thing that does.
+snap ctrl-b-on
 key c-b
 stable 600 8000
 snap ctrl-b-off