`revoke_role` only clears the legacy single-role slot — multi-role addresses can't be individually revoked

[dinahmaccodes]

Tier: Hard
Description: An address can hold multiple roles (e.g. Company then later Guardian) since set_role maintains both a per-role flag map and a single legacy Role(addr) pointer. storage::revoke_role unconditionally resets the legacy pointer, and the public revoke_role only operates on storage::get_role() — never iterating actual per-role flags. There's no way to revoke a non-primary role, and revoking "the" role can leave stale UserRole flags true while get_role reports Unassigned.
Files: contracts/shipment/src/storage.rs:386-393, contracts/shipment/src/lib.rs:1937-1958
Tasks:

• Extend revoke_role to accept and clear a specific role from the per-role flag map, not just the legacy slot
  Acceptance Criteria:
• Any individual role held by a multi-role address can be revoked without desyncing get_role

[best2025j]

@best2025j has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Good day sir, Can I work on this? Perfectly understood

ℹ️ Repo Maintainers: To accept this application, review their application or assign @best2025j to this issue.