I want HD key objects to support deriving children from BIP32-style path strings instead of forcing callers…

I want HD key objects to support deriving children from BIP32-style path strings instead of forcing callers…: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). For example, from the seed 000102030405060708090a0b0c0d0e0f …

The task

For example, from the seed `000102030405060708090a0b0c0d0e0f`, `HD.PrivateKey.fromSeed(seed).derivePath("m/0'").toBase58('main')` should be `xprv9uHRZZhk6KAJC1avXpDAp4MDc3sQKNxDiPvvkX8Br5ngLNv1TxvUxt4cV1rGL5hj6KCesnDYUhd7oWgT11eZG7XnxHrnYeSvkzY7d2bhkJ7`, and `derivePath("m/0'/1/2'/2/1000000000").toBase58('main')`…

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.