Replaces tuple[X, ...] with list[X] throughout UriTemplate internals
and public API. The tuples were defensive immutability nobody needed:
the dataclass fields are compare=False so they do not participate in
hash/eq, and the public properties now return fresh copies so callers
cannot mutate internal state.
Helper function parameters take Sequence[X] where they only iterate;
returns are concrete list[X]. The only remaining tuples are the
fixed-arity (pair) return types on _parse and _split_query_tail, which
is the correct use of tuple.
Max Isbey
278e5e747e