Migrate to oasis sdk#208

Draft

tuhalf wants to merge 3 commits intomasterfrom

migrate-to-oasis-sdk

Commits on Dec 29, 2025

Migrate join contract calls to Oasis SDK (Sapphire) and update dependencies.
tuhalf
committed
Implement timeout handling in RPC response and improve error management
tuhalf
committed

Commits on Dec 31, 2025

Enhance RPC client error handling and refactor SSL usage in newTicket method
tuhalf
committed