store: refusals leave the live books untouched; per-filing names; spec suite

The refusal property gained the converse law (an accepted command
journals something; only batch runs may find nothing to do) and checks
the store's class and payroll listings. It found a schedule registered
with an out-of-range total whose first month was refused after its entry
was begun: the live ledger kept a draft the journal never had.

- Core: compound commands (post_schedule_month, reverse_entry,
  close_period_to, create_invoice, create_bill, receive_payment,
  pay_bill, run_payroll, remit_payroll_taxes) run inside
  Ledger::atomically, so a refusal partway leaves the ledger exactly as
  it was.
- Core: a schedule total no line could carry, or finer than a cent, and
  an asset cost beyond the line range, are refused at registration.
  Replay keeps older schedules (replay_register_schedule).
- Store: add_line, add_line_fx, mark_cleared, set_fx_rate,
  post_schedule_month and close_period_to changed the live ledger before
  journaling; they now run on a copy, journal what it produced, then
  swap it in, so a failed write leaves the live books as journaled.

New spec-blind suite tests/spec_store.rs (57 tests written from the
store's specs alone). Its two findings, adjudicated:
- A file filed twice under different names listed the first name and
  type for both (the projection kept them per blob). Schema v8 gives
  each attachment its own; older databases backfill and heal by verify.
- Withdrawn attachments stay in the store's listing, marked (the MCP
  listing hides them): the spec and doc said "omit" and are corrected.

Also removes journal::truncate_to_last_good_seq: unused, and it dropped
everything after the first bad complete line, which the books now treat
as corruption for a person, never repaired automatically.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX

fuzz/Cargo.toml

@@ -57,3 +57,10 @@ path = "fuzz_targets/fuzz_store_open.rs"
 test = false
 doc = false
 bench = false
+
+[[bin]]
+name = "fuzz_store_replay"
+path = "fuzz_targets/fuzz_store_replay.rs"
+test = false
+doc = false
+bench = false