Improve Conformance definitions in ZAP XML with Alchemy

[ethanzhouyc]

ZAP cluster XMLs currently define conformance in two redundant ways:
1. The optional attribute (e.g. optional="true").
2. Conformance tags (e.g. <mandatoryConform>).

To solve the problem, Alchemy should be updated to:

1. Generate conformance data for all elements in the standardized <xxxConform> format.
2. Remove reliance on optional=true once all elements are migrated.
3. Address any other necessary fixes to improve conformance handling.

Before proceeding with full transition, discussion with the Alchemy and CSA teams are necessary to determine the best approach. The goal is to align ZAP XML generation with a single conformance mechanism.