feat: fund identity registration and top-up from the wallet's own Core coins

[LexxXell]

Draft. Depends on #167 (dash-platform-sdk 1.5.0-dev.10): the fee estimate uses StateTransition.calculateMinRequiredFee() from pshenmic-dpp 2.0.0-dev.29, so this does not compile on develop's SDK yet. Will be rebased once #167 is merged.

Changes

Identity registration and top-up paid from the wallet's own Core coins (BIP44 UTXOs), instead of a deposit to a one-off funding address. Backend only; Platform-address and shielded sources come in later PRs.

The flow is split into a quote and a confirmation, both journaled so that any step can be resumed after a crash, a closed popup or a network timeout without reselecting coins or spending a second asset lock:

1. PREPARE_IDENTITY_FUNDING selects UTXOs, reserves the DIP-13 index (registration 5'/1'/i, top-up 5'/2'/i), signs the asset lock and estimates the Platform fee. Nothing is broadcast. Returns the operation with Core and Platform fees and the expected net credits.
2. REGISTER_IDENTITY_FROM_CORE / TOP_UP_IDENTITY_FROM_CORE broadcast the saved asset lock, wait for its InstantLock/ChainLock proof, build and send the identity transition, and wait for Platform to confirm it.
3. CANCEL_IDENTITY_FUNDING releases a quote that has not been broadcast. GET_IDENTITY_FUNDING_OPERATIONS / GET_IDENTITY_FUNDING_SOURCES list operations and the spendable Core balance.

Backend pieces

• IdentityFundingRepository — per-wallet journal (identityFunding_<network>_<walletId>), guarded by Web Locks: a short journal lock for writes and a per-operation lock for a whole execution.
• IdentityFundingService — domain primitives (UTXO loading via dashscan /xpub/utxo, parent tx verification, signing, fee estimate, broadcast, transition building); the handlers orchestrate them.
• buildAssetLockFromUtxos — multi-input asset lock with change back to the BIP44 change chain (1 duff/byte, 546 dust).
• Error handling (identityFundingErrors):
  • an unknown outcome (timeout, deadline elapsed, network) keeps the operation pending;
  • a Core tx the network refused releases the coins;
  • a Platform rejection of a transition on an asset lock that is already on L1 retries on the same lock with a ChainLock proof. The Core tx is never rebroadcast after it was accepted.
• REGISTER_IDENTITY is refused while a registration funding operation is pending.
• Migration 0010 (schema 10) only bumps the version; the journal lives under new keys.

Testing

• tsc --noEmit, ts-standard (on dev.10)
• jest: 361/362 on dev.10 (exportPrivateKey times out only in the full run and passes alone)
• Live on testnet from the dev console: Core registration and top-up, 13/13 checks; the Core fee matched the quote exactly.

[LexxXell]

Superseded by #177. The funding journal chain is parked on the archive/identityFundingJournal branch.