A middle or right sweep over a column's or the workspace's tag runs or looks for what it swept, as a pane tag's does

Both headers acted on the press: a middle or right press ran, or looked
for, the word under it (or the header's selection when it was on that) at
once, so a drag had nothing left to do. A sweep of `echo SWEPT` in a column
tag ran a bare `echo`. They have done so since the headers were drawn apart
from the panes; it is no regression, and the -l/Restore allocator fix
(ompukopz) does not touch it.

Now a press on a header holds a HeaderSweep (the column by its serial, or
the workspace), which the drag extends, held to the header's row and text
as a pane tag's sweep is. It is painted in its button's tint meanwhile, and
the release runs what it swept in that header's context; a release that has
not moved runs the word or selection a click always did. The other of
middle and right cancels it (acme 2-3/3-2); the select button is inert, as
a header's command already takes the held selection as its argument.

Running on the release, a builtin from a header is announced as one from a
pane tag is: the press used to set the announcement and the release clear it
at once. find, restore, theme, topbarexec, ttyhelp, tutor and windowops
re-recorded for that badge alone.

headersweep.snap sweeps the column and workspace tags with the middle
button and a word part with the right one, and cancels a sweep;
headersweep-restored.snap sweeps both after Dump and Restore.

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

1 files changed, 42 insertions, 0 deletions

diff --git a/test/snapshots/headersweep-restored.snap b/test/snapshots/headersweep-restored.snap
new file mode 100644
index 00000000..c2918e1a
--- /dev/null
+++ b/test/snapshots/headersweep-restored.snap
@@ -0,0 +1,42 @@
+# headersweep.snap in a session restored from a dump: its column and
+# workspace tags are rebuilt, and a middle sweep over each runs what it
+# swept, as it does in a fresh session.
+start 21 120 -n 3
+wait 8000 Newcol
+stable 700 20000
+press middle @Dump 1
+release middle @Dump 1
+stable 700 10000
+press middle @Restore 1
+release middle @Restore 1
+stable 900 15000
+press left 50 2
+release left 50 2
+key space
+text echo RE''STORED-COL
+key esc
+settle 100
+press middle @echo 2
+drag middle @echo+8 2
+stable 300 5000
+snapstyle col-sweeping
+drag middle @echo+19 2
+release middle @echo+19 2
+wait 8000 RESTORED-COL
+stable 700 15000
+snap col-swept
+press left 118 1
+release left 118 1
+key space
+text echo RE''STORED-WS
+key esc
+settle 100
+press middle @echo 1
+drag middle @echo+8 1
+stable 300 5000
+snapstyle ws-sweeping
+drag middle @echo+18 1
+release middle @echo+18 1
+wait 8000 RESTORED-WS
+stable 700 15000
+snap ws-swept