refactor: unify account info error boundary

[ovitrif]

Closes #96

Description

This PR applies the run_account_info_blocking boundary from the address-info hotfix to the remaining onchain BDK/Electrum paths that return AccountInfoError:

• get_account_info
• get_transaction_history
• get_transaction_detail
• compose_transaction

Inner typed AccountInfoError values are preserved, while blocking-task panics and join failures now return AccountInfoError::SyncError through the same helper used by get_address_info.

Release:

• v0.1.68

Preview

N/A, native library change.

QA Notes

Automated Tests

• cargo fmt --check
• cargo test account_info_blocking_task -- --nocapture
• cargo test compose_empty_fee_rates -- --nocapture
• cargo test get_transaction_history_invalid_key -- --nocapture
• cargo test get_transaction_history_network_mismatch -- --nocapture
• cargo test get_transaction_detail_invalid_key -- --nocapture
• cargo test get_transaction_detail_invalid_txid -- --nocapture
• cargo test get_transaction_detail_network_mismatch -- --nocapture
• cargo test get_account_info_invalid_key -- --nocapture
• cargo test get_account_info_network_mismatch -- --nocapture
• cargo test --lib -- --skip modules::blocktank
• cargo clippy (passes with existing warnings)
• ./build.sh -r --patch all
• ./build.sh all
• swift package compute-checksum bindings/ios/BitkitCore.xcframework.zip

Release Notes

• Bumped bitkit-core to 0.1.68.
• Regenerated Android, iOS, and Python native artifacts.
• Published v0.1.68 at 75bf69e;