Uniqueness of the paper's reduced banana coordinates #
This is the uniqueness layer in Proposition 2.14. Two preferred position vectors differing by the displayed lattice first give linearly equivalent left-reduced divisors, hence equal divisors by uniqueness of q-reduction.
The q-reduced core of uniqueness: displayed-equivalent paper representatives have exactly the same position-coordinate divisor.
Equality of position-coordinate divisors remembers the semibreak chip on each individual strand, despite the common endpoint aliases.
An interior coordinate is recovered strand-by-strand from the associated position-coordinate divisor.
The apparent endpoint aliases do not create a second preferred representative: the ordering clause makes the endpoint assignment unique.
Full uniqueness/injectivity statement for Proposition 2.14.