Make a pane's tag a Text edited with the body's own keys

The tag was a fixed buffer with its own one-line editor, a cursor measured
across the path, and a hijack of the body's mode while it was typed into.
It is now the pane's second Text: its own characters after the computed
prefix (path, dirty marker, PDF page), which is never stored in it, so a
rename or a dirty marker never moves its cursor. Normal and insert mode are
the body's, undo included; `:` moves the keyboard between body and tag, the
tag remembers its cursor and starts on Save, and executing a word from it
hands the keyboard back. The mouse still sees the prefix: a sweep selects
across it and a click on the path drafts a new name.

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

1 files changed, 37 insertions, 99 deletions

diff --git a/test/snapshots/tagnav.snap b/test/snapshots/tagnav.snap
index c375e644..eed808de 100644
--- a/test/snapshots/tagnav.snap
+++ b/test/snapshots/tagnav.snap
@@ -1,25 +1,22 @@
-# h/j/k/l ON A TAGLINE move focus BETWEEN taglines. A tag is a place in the
-# LAYOUT, not just a line of text, so the four letters walk the layout and land
-# on the neighbour's TAG (top row of the window), still in normal mode — you
-# walk the taglines and never drop through a body. They run the SAME
-# Left/Down/Up/Right builtins `SPC w h/j/k/l` and `Ctrl-w h/j/k/l` run: one
-# focusDir, three routes to it. The ARROWS keep the in-tag grapheme motion, so
-# no capability was traded away.
+# A tag's normal mode is the body's: h/l/w move in the tag's own text, and
+# moving between panes is the window keys' job from a tag as from a body --
+# there are no tag-only hops. `:` is the one key a tag and a body do not
+# share: from the body it focuses the pane's own tag, from the tag it hands the
+# keyboard back to the body. Each tag remembers its cursor; the first time
+# there is nothing to remember and it starts on Save.
 #
 # Evidence is the `cursor=` header (the ACTIVE pane's cursor, which while a tag
 # is focused sits on THAT pane's tag row) plus each pane's layout box, which
-# carries its BODY mode as one character: `•` normal, `^` insert, `$` tty. A
-# tag edit parks the body mode rather than overwriting it, so the box keeps
-# saying what the pane we left will be when we hop back off its tagline.
+# carries its BODY mode as one character: ` ` normal, `^` insert, `$` tty. The
+# tag has a mode of its own, so the box never changes while a tag is used.
 file w.txt alpha\nbeta\ngamma
 start 31 100 w.txt
 wait 8000 Newcol Joincol
 wait 8000 w.txt
 stable 700 20000
-# A FILE boots alone now, so the shell this script calls "the launch shell" is
-# opened here: Alt-n opens it and focuses it, Alt-c puts it in a column of its
-# own on the right, SPC w h comes back to the file. (`New`/`Newcol` open an
-# empty +New scratch now, not a shell.)
+# A FILE boots alone, so the launch shell is opened here: Alt-n opens it and
+# focuses it, Alt-c puts it in a column of its own on the right, SPC w h comes
+# back to the file.
 key a-n
 key a-c
 stable 700 15000
@@ -32,110 +29,51 @@ stable 700 15000
 key space w k
 stable 400 5000
 snap start
-# `:` -> the file's OWN tagline, normal mode, parked at the tail's start
+# `:` -> the file's OWN tagline, normal mode, on Save
 key :
 stable 400 5000
 snap colon
-# l -> right, onto the launch shell's TAGLINE (not its body)
-key l
-stable 400 5000
-snap right-tag
-# h -> back left onto the file's tagline
-key h
-stable 400 5000
-snap left-tag
-# j -> down onto the tagline of the shell under the file
-key j
-stable 400 5000
-snap down-tag
-# k -> back up onto the file's
-key k
-stable 400 5000
-snap up-tag
-# k visits the column tag first, then the workspace tag. Both stay in normal
-# navigation mode; neither hop drops into a pane body.
-key k
-stable 400 5000
-snap column-tag
-key k
-stable 400 5000
-snap up-edge
-# the bar speaks the tag's own one-line vocabulary: w to the next word start
+# w selects in the tag the way it selects in a body
 key w
 stable 400 5000
-snap topbar-word
-# h/l are plain graphemes up here — row 0 has no window to its left or right to
-# walk to — and the arrows still mean what they always did
-key l right
+snap word
+# l is a motion in the tag, not a hop to the next pane
+key l l
 stable 400 5000
-snap topbar-graphemes
-# j is the mirror of the k that got you here: back DOWN onto the topmost pane's
-# tagline, still in normal mode, so the hop is a round trip
-key j
+snap in-tag
+# the window keys move between panes from a tag as from a body: the tag lets
+# go and the neighbour's BODY takes the keyboard
+key c-w l
+stable 400 5000
+snap right
+# `:` there -> that pane's own tag, on its Save the first time
+key :
 stable 400 5000
-snap column-down
-key j
+snap right-tag
+# back left, and `:` finds the file's tag cursor where l left it
+key c-w h
 stable 400 5000
-snap back-down
-# the arrows are still in-tag motion: two rights walk two columns of the tail
-key right right
+key :
 stable 400 5000
-snap arrows-still-motion
-key esc
-settle 100
+snap left-tag
+# `:` in the tag's normal mode: back to the body
+key :
 stable 400 5000
 snap back-to-body
-# A TERMINAL MUST NOT LOSE ITS TTY MODE. Put the launch shell in raw tty mode
-# (Ctrl-b), come back, then hop onto its tagline and off again: exitTagEdit
-# restores the body mode the tag hijacked, and its box reads `$` throughout —
-# during the hop too, because the box shows the PARKED mode, not the tag's.
+# A TERMINAL KEEPS ITS TTY MODE. Put the launch shell in raw tty mode (Ctrl-b),
+# click its tagline and come back: its box reads `$` throughout, because the
+# tag's mode is the tag's own.
 key c-w l
 stable 400 5000
 key c-b
 stable 700 15000
 snap tty-on
-key c-w h
-stable 400 5000
-key :
-key l
+press left @Mode 3
+release left @Mode 3
 stable 400 5000
 snap tty-tag
 key esc
 settle 100
-stable 400 5000
-snap tty-restored
-# Enter/Tab on the BAR runs the word under the cursor through the very dispatch
-# a middle click on it uses, and leaves the bar FIRST — `Kill` lives up here, so
-# a builtin that frees the session must never return into a focused topbar (the
-# same hazard the pane-tag chord has with `Del`). `$` proves the destructive
-# word is exactly last; four long-word steps back land on `Dump`, the visible
-# non-destructive action used here. It grows a `Restore <path>` word, which is
-# also the case where the line gets longer than the column you were parked on.
-key c-w h
-stable 400 5000
-key :
-key k k
-stable 400 5000
-key $
-stable 400 5000
-snap topbar-dollar
-key B B B B
-stable 400 5000
-snap topbar-dump-word
-key enter
-stable 700 15000
-snap topbar-exec
-# THE DELETION HAZARD, from the bar itself: `Restore` frees every pane and
-# swaps the core out from under the caller. Walk back onto the word the Dump
-# just grew — B twice off the tail, because the LONG word motions are the ones
-# that step over a path in one go — and run it. The bar drops focus BEFORE the
-# builtin, so nothing reaches for state the swap already freed.
 key :
-key k k
 stable 400 5000
-key $ B B
-stable 400 5000
-snap topbar-restore-word
-key enter
-stable 900 15000
-snap topbar-restored
+snap tty-restored