feat: bound family wallet transaction archive and verify selection bo…

[ScriptedBro]

Summary

Closes #643

This pull request implements bounded transaction archiving for the family_wallet contract. The archive mechanism ensures that ARCH_TX never grows unbounded, preventing instance-storage rent inflation. It also adds proper ArchiveEvent emission consistency and comprehensive documentation.

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Changes

• family_wallet/src/lib.rs:

  • Updated archive_old_transactions to emit ArchiveEvent::TransactionsArchived instead of RemitwiseEvents::emit
  • Updated cleanup_expired_pending to emit ArchiveEvent::ExpiredCleaned instead of RemitwiseEvents::emit
  • Updated cancel_transaction to emit ArchiveEvent::TransactionCancelled (previously had no event emission)
  • Archive enforces strict less-than boundary check (executed_at < before_timestamp)
  • Archive bounded at MAX_ARCHIVE_ENTRIES (500) with oldest-first eviction
  • Updates STOR_STAT.archived_transactions after archiving

• docs/fw-archive-lifecycle.md:

  • Created comprehensive documentation of the archive lifecycle
  • Documents key functions, storage bounds, data integrity, and security considerations
  • Lists all test coverage for archive invariants

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Test Output

test result: ok. 150 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 21.19s