40858cbc11
- TX builder: emit per-output ephemeral keys (tag 0x04) for CARROT TXs
instead of single shared key (tag 0x01)
- Wallet: add subaddress/account creation, labeling, integrated address
encode/decode, and bump lookahead from 50 to 10,000
- DB: add subaddresses table with upsert/query/label/mark-used methods
- FFI: add wallet blob export/import/rekey (PQC-encrypted)
- CI: add WASM build target to release workflow