PPLR's SemanticTreeLegend (a diverged copy of the library's; retiring it is card
RETIRE-PPLR-SEMANTICTREELEGEND) still typed in five strings: "Loading {label}…",
"Loading data…", "No data at this level", "Showing top {n} of {m}" and "use the
geocoder above to find the rest". The keys exist in all 11 locales since
d4359163 (legend.loadingRows / loadingData / noDataAtThisLevel / showingTop /
useGeocoderHint), which the library copy uses.
They now go through the component's existing guarded translator (ta), with the
English added to its fallback table, so a host without i18n still reads
English, never a key. Numbers keep their current toLocaleString (numerals held).
Headless: build OK, and check:no-free-identifiers, i18n-parity and
profiles-mount pass. (check:ui-strings-have-keys, which found this, is not on
main yet.)