hexify_z7_canonical: Get canonical form of Z7 index
Description
For Z7 indices that form cycles during decode/encode, returns the
lexicographically smallest index in the cycle. Provides stable
unique identifiers for aperture 7 grids.
Usage
hexify_z7_canonical(index, max_iterations = 128L)
Value
Canonical form (lexicographically smallest in cycle)
Arguments
index
Z7 index string
max_iterations
Maximum iterations for cycle detection (default 128)