feat: real dates and per-account detail in every statement export

Every statement export rendered life-of-ledger totals under whatever date
range or as-of label was asked for, and the P&L and balance sheet XLSX
were totals-only. Now:

- books.profit_and_loss / books.balance_sheet and the csv, json, xlsx,
  pdf exports and CPA package all use core's profit_and_loss_for_period
  and balance_sheet_as_of, with a line per account. The tools keep their
  totals and add revenue/expense/asset/liability/equity account lines.
  An omitted start is the first posted entry, never "0001-01-01".
- ledger-import::report lays a statement out once (section, line,
  subtotal, total) for every renderer, with one exact amount formatter:
  thousands separators, negatives in parentheses, no floats. XLSX keeps
  numeric cells with an accounting number format, named sheets, company
  header, totals with borders; the trial balance gains its totals row.
- ledger-mcp reads wanderbooks.toml (next to --data-dir, or
  --books-toml): company name for headers, fiscal_year_start for the CPA
  package's fiscal year to date (end derived; Feb 29 rejected), and
  [books] receipt_threshold, which the server had been ignoring.
  config.json's receipt_policy still wins when set. New dependency: toml
  1.x (already in the lockfile via another crate).
- Store::journal_seq(); every report notes the journal seq it reflects.

Tests: company.rs unit tests (fiscal years incl. a July start, scaffold
parsing, bad settings); report.rs formatting tests; an MCP stdio test with
--books-toml (threshold 5.00 enforced, February-only P&L with account
lines, start defaults to the first entry, as-of balance sheet).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MtYEaR6M6Ybdhm6X98BWNu

plan/STATUS.md

@@ -170,3 +170,11 @@ interface is MCP, not a cloned GUI. The first storage + MCP slice is done
   requested label; core needs period-scoped statements); P&L and balance
   sheet XLSX are totals-only; PDF amounts don't align (padding in a
   proportional font), no company name, negatives as "-x".
+- 2026-10-11: Every statement export (csv, json, xlsx, pdf, CPA package)
+  now renders core's period statements: the date range and as-of date are
+  real, with a line per account. One layout (`ledger-import::report`:
+  sections, lines, subtotals, totals; exact "(1,234.56)" formatting) feeds
+  every renderer. The server reads `wanderbooks.toml`: company name for
+  report headers, `fiscal_year_start` for fiscal YTD (end derived), and
+  `receipt_threshold` (it was silently ignored before). Reports carry
+  "Prepared from journal through seq N".