Add an encrypted SQLite transaction history cache with cached tip metadata and
per-address shielded scan progress so startup and full refreshes avoid
re-scanning every z-address while still invalidating on wallet/address/rescan
changes.
Improve wallet history loading by paging transparent transactions, preserving
cached shielded and sent rows, keeping recent/unconfirmed activity visible, and
classifying mining-address receives. Show z_sendmany opid sends immediately in
History and Overview, pin pending rows through refreshes, and apply optimistic
address/balance debits until opids resolve.
Add timestamped RPC console tracing by source/method without logging params or
results, reduce redundant refresh/RPC calls, and cache Explorer recent block
summaries in SQLite.
Expand focused tests for transaction cache encryption, scan-progress
persistence/invalidation, history preservation, operation-status parsing,
pending send visibility, and Explorer/RPC refresh behavior.
Replay cached outgoing viewtransaction entries during transaction refresh so shielded sends created from the wallet remain in the History tab after send tracking is cleared.
Keep incomplete tracked sends retryable, preserve cached send timestamp/confirmation metadata, and emit a send placeholder from gettransaction metadata when viewtransaction enrichment is not yet available.
Add regression coverage for cached sends, retryable empty entries, placeholder sends, and send txid cleanup behavior.
