Esc alternates between the last two panes; Toggleterm is gone

Esc ran Toggleterm, which hopped between the newest DOC and the newest
TERMINAL. That distinction never earned its keep. It made Esc unpredictable —
which of three panes you landed on depended on their kinds, not on where you
had been — and it could not alternate between two files at all, which is the
case you hit most. Editing two files, Esc did nothing.

The replacement already existed. Last (SPC j j) is "the pane you were in
before this one, whichever it was": it walks the jump stack for the newest
entry naming a different pane and restores its line and column. So Esc, and
Shift-Esc in tty, now run Last, and Toggleterm is deleted rather than renamed
— a third implementation of "go to the other pane" was the thing to avoid.
SPC w t goes with it; the w group is the four directional moves, and the jump
group already had SPC j j.

Held down, Esc alternates. Two files, a file and its shell, a file and a
+Search — all the same, because Last has no notion of kind to get wrong.

This depends on the swap in the same series: Last reads the stack backwards,
and until hopping stopped appending, the pane you came from could fall off it.

windownav.snap needed only its keys and prose changed — its golden did not
move at all, which is the useful evidence here: for the one scenario the old
builtin handled well, Last produces an identical focus sequence.

Coverage for what it did not handle is new: a unit test opens a second FILE by
looking its name and asserts Esc alternates between two panes of the SAME
kind, which is the case that used to be a no-op.

Docs follow: tutor.txt, docs/helix-keys.md, docs/design.typ, and the builtin
index goldens, which are now one row shorter.

75/75 snapshots, both unit suites, and the macOS ABI build all pass.

1 files changed, 20 insertions, 20 deletions

diff --git a/test/snapshots/fsearch.golden b/test/snapshots/fsearch.golden
index 08132e28..8de3f0e7 100644
--- a/test/snapshots/fsearch.golden
+++ b/test/snapshots/fsearch.golden
@@ -1,6 +1,6 @@
 == snap opened grid=180x30 cursor=7,2
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -15,7 +15,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -31,7 +31,7 @@
 |
 == snap typing grid=180x30 cursor=8,29
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -46,7 +46,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -62,7 +62,7 @@
 |   /MARK
 == snap results grid=180x30 cursor=7,2
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -77,7 +77,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -93,7 +93,7 @@
 |     3 g.txt:10:1-4 MARK c
 == snap first grid=180x30 cursor=10,3
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -108,7 +108,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -124,7 +124,7 @@
 |     3 g.txt:10:1-4 MARK c
 == style first
 |0: 0-56 #949494,#121212, 57-179 d,#121212,
-|1: 0-1 #ffffff,#626262, 2-48 #949494,#121212, 49-59 d,#121212, 60-61 #ffffff,#262626, 62-97 #949494,#121212, 98-119 d,#121212, 120-121 #ffffff,#262626, 122-157 #949494,#121212, 158-179 d,#121212,
+|1: 0-1 #ffffff,#626262, 2-48 #949494,#121212, 49-59 d,#121212, 60-61 #ffffff,#262626, 62-99 #949494,#121212, 100-119 d,#121212, 120-121 #ffffff,#262626, 122-159 #949494,#121212, 160-179 d,#121212,
 |2: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-8 #bdbdbd,#080808, 9-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |3: 0-0 d,#444444, 1-1 d,#080808, 2-6 #949494,#121212, 7-10 #080808,#80a0ff, 11-12 #bdbdbd,#080808, 13-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |4: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-8 #bdbdbd,#080808, 9-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
@@ -139,7 +139,7 @@
 |13: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-9 #bdbdbd,#080808, 10-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |14: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |15: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
-|16: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-61 #ffffff,#262626, 62-97 #949494,#121212, 98-119 d,#121212, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
+|16: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-61 #ffffff,#262626, 62-99 #949494,#121212, 100-119 d,#121212, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |17: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |18: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 |19: 0-0 d,#444444, 1-1 d,#080808, 2-6 #626262,#080808, 7-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
@@ -155,7 +155,7 @@
 |29: 0-0 d,#121212, 1-1 d,#080808, 2-6 #626262,#080808, 7-25 #bdbdbd,#080808, 26-59 d,#080808, 60-60 d,#444444, 61-61 d,#080808, 62-119 #bdbdbd,#080808, 120-120 d,#444444, 121-121 d,#080808, 122-179 #bdbdbd,#080808,
 == snap second grid=180x30 cursor=10,7
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -170,7 +170,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -186,7 +186,7 @@
 |     3 g.txt:10:1-4 MARK c
 == snap third grid=180x30 cursor=10,11
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -201,7 +201,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -217,7 +217,7 @@
 |     3 g.txt:10:1-4 MARK c
 == snap back grid=180x30 cursor=10,7
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -232,7 +232,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -248,7 +248,7 @@
 |     3 g.txt:10:1-4 MARK c
 == snap cancel grid=180x30 cursor=10,7
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -263,7 +263,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |
@@ -279,7 +279,7 @@
 |     3 g.txt:10:1-4 MARK c
 == snap nomatch grid=180x30 cursor=10,7
 |New Newcol Find Grep Help Tutor Dump NextColor Debug Kill
-|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd New Del                        /tmp/pardes-snap/fsearch/cwd New Del
+|  /tmp/pardes-snap/fsearch/cwd/g.txt Save New Del             /tmp/pardes-snap/fsearch/cwd   New Del                      /tmp/pardes-snap/fsearch/cwd   New Del
 |     1 l1
 |     2 MARK a                                                 g.txt                                                       g.txt
 |     3 l3
@@ -294,7 +294,7 @@
 |    12 l12
 |
 |
-|                                                              /tmp/pardes-snap/fsearch/cwd New Del
+|                                                              /tmp/pardes-snap/fsearch/cwd   New Del
 |
 |                                                              g.txt
 |