feat(platform): move to rust-dashcore dev and decode Core v24 shared masternode transactions (types 10, 11, 12) #5437

Platform 5.0 pins rust-dashcore's integration/v5.0-core-v24 branch, which decodes the Core v24 shared-masternode special transaction types 10, 11 and 12 as raw payloads only. rust-dashcore dev now decodes and encodes them (dashpay/rust-dashcore#1156), plus the related breaking changes (#1157 asset unlock v2 txid and instance hash, #1160 consensus params, #1175 payload serde index).

For 5.1: move Platform to rust-dashcore dev, use the structured payloads where Platform, the SDKs and the wallets read these transactions, and drop the integration branch. Behaviour at protocol versions up to 14 must not change.

The forward merge of v5.0-dev into v5.1-dev starts this move (the rust-dashcore pin has to go to dev there).