Translate every Italian /// XML doc comment, <!-- --> XAML comment, and
// inline comment to English across all source files (Core, App, tests).
Add the language policy to CLAUDE.md (conversation Italian; all code
and docs English). Update one test assertion that checked an Italian
exception message that was also translated.
Speed up wallet synchronization, especially re-syncs of large wallets:
- Incremental address discovery: known indices from the previous sync
(NextReceiveIndex/NextChangeIndex) are fetched in a single parallel
burst instead of sequential gap-limit rounds, cutting round-trips from
O(used/gapLimit) to ~O(1). Receive and change chains scan in parallel.
- Merge tx download and Merkle verification into one parallel phase
(no barrier between them); the per-call semaphore is dropped in favor
of the transport-level in-flight gate.
- Persist verified block headers (SyncCache.BlockHeaders, height -> hex):
immutable once stored, so blockchain.block.header round-trips for
already-verified proofs are eliminated on later syncs.
- RetryOnBusyAsync with exponential backoff around server calls, treating
-101/-102 and "server busy"/"excessive resource usage" as transient.
Wire the new PreloadCaches/ExportCaches signatures through the desktop
view model and the CLI sync command.
Three interrelated fixes for sync reliability on large wallets:
1. Prevent -101 "excessive resource usage":
ScanChainAsync uses GetHistoryAsync for discovery instead of
SubscribeScripthashAsync. Subscriptions are limited to the gap window
only (≤ 2×gapLimit addresses), so the session subscription count stays
constant regardless of wallet history size — eliminating -101 on
wallets with 1000+ historical addresses.
2. Persist and resume tx cache across sessions and disconnects:
WalletSynchronizer gains ExportCaches() and PreloadCaches(). On every
successful sync (and on partial failure) the downloaded raw tx hex and
verified Merkle heights are written to SyncCache.RawTxHex/VerifiedAt
in the wallet file. On reconnect or app restart the new synchronizer
is pre-populated from disk so only new transactions are downloaded.
_synchronizer is always nulled on reconnect (new client = new instance)
while caches survive via the wallet file.
3. Auto-connect with multi-server fallback and retry:
ConnectAndSync iterates BuildServerCandidates() (current server first,
then all KnownServers in order) and stops at the first that responds.
_autoReconnect and _syncFailed are set in OpenLoaded() so the keepalive
timer (20 s) retries automatically on any failure — connection error,
-101 mid-download, or timeout. PersistPartialTxCache() saves whatever
was downloaded so each retry resumes from its checkpoint.
WalletSynchronizer now pipelines JSON-RPC requests (address subscribes,
histories, tx downloads and Merkle proofs run in parallel batches) and
keeps per-connection caches of downloaded transactions and verified
proofs, so notification-triggered resyncs only cost the delta.
The app connects automatically when a wallet opens, keeps one
synchronizer per connection, and queues notifications that arrive
during a sync instead of dropping them: incoming transactions now show
up within seconds.
davide