Give the usage bars a line of their own, always

Squeezing the 5h/7d group onto line one was what cost the reset times and
the pace figure at laptop width, and it made the layout jump between one
and two lines as the branch name or the cost changed width. Line two is
now the group's own at every terminal size, so both timestamps and the
burn rate fit; the ladder only starts giving things up below ~80 columns.

The bars also survive down to 35 columns now rather than being dropped
below 68, since a line of their own is all they need. Every rung of the
ladder is fit-checked, the last one included: with the floor that low, a
percentage the API reports in more digits than anyone expects would
otherwise have overflowed the line rather than dropped the group.

The two timestamps still cost ~10 subprocesses to format on a line that
redraws per keystroke, so that is skipped when line two provably cannot
show them -- an under-estimate, so the fit check stays the decider.

With nothing left to squeeze, WRAP_NARROW, the wrap band and the split
tier go: line one is the full tier down to 150, wide to 68, then narrow.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

claude/tests/statusline.isaacaudet.thinking_test.sh

@@ -82,8 +82,10 @@ echo "Fallbacks and tiers:"
 has  true  ""     "◆ thinking" 200 "absent effort falls back to the old label"
 has  true  garbage "◆ thinking" 200 "an unrecognised level falls back rather than widening the line"
 has  true  high    "◆ high"     120 "the label survives the wide tier"
-# The split tier (76-99) is unreachable while WRAP_NARROW=true -- that band is
-# overridden to wide and wrapped -- so only narrow is asserted here.
+# Below 68 columns the narrow tier drops the segment entirely; between there
+# and 100 the compact tier keeps the label, since the usage group has moved off
+# line one and left room for it.
+has  true  high    "◆ high"     85  "the label survives the compact tier"
 lacks true  high   "◆"           60  "narrow tier hides the segment"
 
 echo