window navigation builtins: SPC w h/j/k/l focus, SPC w t file<->terminal

Left/Down/Up/Right run the existing focusDir (now taking the pane the
builtin ran on, so an executed name acts on ITS pane); the Ctrl-w prefix
routes through the same four builtins instead of calling focusDir itself.
Toggleterm hops between the most recently focused document and terminal
off focus_hist, the MRU the core already rebuilds each sync.

Ctrl-w stays: a tty-mode pane never sees SPC, so it is the only keyboard
way out of one. Its snapshot step now moves focus somewhere (c-w l), which
the old c-w h in that layout did not.

1 files changed, 310 insertions, 0 deletions

diff --git a/test/snapshots/windownav.golden b/test/snapshots/windownav.golden
new file mode 100644
index 00000000..3017fa29
--- /dev/null
+++ b/test/snapshots/windownav.golden
@@ -0,0 +1,310 @@
+== snap start grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+== snap to-term grid=100x30 cursor=54,4
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+== snap back-to-file grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+== snap altn grid=100x30 cursor=4,19
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+|  w.txt
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+== snap up grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+== snap right grid=100x30 cursor=54,4
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+== snap left grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+== snap down grid=100x30 cursor=4,19
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+== snap toggle-doc grid=100x30 cursor=7,2
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+== snap toggle-back grid=100x30 cursor=4,19
+|Kill Newcol Tutor Debug Colors NextColor Crt Dump
+|  NOR /tmp/pardes-snap/windownav/cwd/w.txt Save De  NOR /tmp/pardes-snap/windownav/cwd Del
+|     1 alpha
+|     2 beta                                         w.txt
+|     3 gamma
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+|  NOR /tmp/pardes-snap/windownav/cwd Del
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+|  w.txt
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