querySubstitutionFeatures
Queries the substitution features available in the specified font face for a given script.
Substitution features define how characters or glyphs are replaced or altered in the text shaping process for the specified script. This method returns a list of feature identifiers that represent the supported substitution capabilities.
Return
a list of strings, where each string is an identifier of a supported substitution feature.
Parameters
face
the font face to query. This specifies the source of typographic data and capabilities.
script
the script for which substitution features are being queried. It determines the writing system context (e.g., Latin, Arabic, Chinese).