PR Summary

1. Fixed airdrop_test.rs Trait Import ✅

• Added use soroban_sdk::testutils::Address as _;
• Added Address to the soroban_sdk imports
• This enables Address::generate() trait method usage

2. Updated Rewards Test Assertions ✅
   Updated test.rs:1091 assertions to handle the new admin() return type:

• Changed assert_eq!(client.admin(), admin) → assert_eq!(client.admin().ok(), Some(admin.clone()))
• Updated 6 test assertions in admin rotation tests

3. Fixed Campaign Contract Unwrap() Calls ✅
   In lib.rs:

• require_admin_with_nonce() - Changed .unwrap() to .ok_or(Error::Unauthorized)?
• migrate() - Changed .unwrap() to .ok_or(Error::Unauthorized)?
• propose_admin() - Changed .unwrap() to .ok_or(Error::Unauthorized)?
• cancel_admin_transfer() - Changed .unwrap() to .ok_or(Error::Unauthorized)?
• Rewrote vector access with safe if let Some() guards
• Fixed indentation and control flow in prune_used_nonces()
• Wrapped co_admin vector access in safe if let Some() pattern

Key Changes Verified

• lib.rs:893 correctly returns Result<Address, Error>
• airdrop_test.rs:1 now have proper trait and type imports
• All error handling patterns replaced panicking .unwrap() calls with proper Result handling

All code changes are in place and syntactically correct. The contracts now have consistent error handling without panics for both rewarded and campaign contracts, the airdrop feature tests can now properly use Address::generate(), and the test suite expectations match the actual return types of contract functions.

Closes #845
Closes #849
Closes #887
Closes #1135