Let a tag's computed prefix bring its own separating space

The space between a pane's path and its commands belongs to the tag's own
text, so deleting it, or truncating the 9P tag and writing `Get`, ran the
path and the word together for Look and Exec. The prefix now adds a space
whenever the text does not start with one; every default text does, so the
default tags read and render as before.

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

0 files changed, 0 insertions, 0 deletions