`fit_measure` concatenates three warning tiers with two `splice(0..0, ..)`
calls. The resulting order — the budget's notices, then the feature table's,
then preprocess's — is stated in the field's doc comment and in
context/code/gp.md section 14, joined into a user-facing status line, and was
checked nowhere: swapping the two statements left all 74 improvise-gp tests
green.
No pre-existing fixture produced more than one tier, which is why nothing caught
it. `all_three_warning_tiers_at_once` adds two things to the wide-category
fixture: a `_Measure` item with no cell anywhere (a header column entirely
missing in every row, which preprocess warns about) and a `Cost` cell at an
unused coordinate (one visible record with no `Score`, which feature_table
skips). Neither disturbs the budget arithmetic.
The assertion is on the three positions, not on the concatenation containing
them, and the helper panics on an absent tier so a tier that stops speaking
fails loudly rather than making the ordering trivially true. Two rivals, each
moving a different boundary, each caught only by this test.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FC2jVn8Au7E9JPkw6bwXXH
Edward Langley
17a582ae4d