P3 review: P2 can read the books until the owner consents

A schedule-convention setting, the two new tax categories, a disposal
before the in-service date and a depreciation catch-up each need their
feature now (tax_categories_gain_exempt, disposal_before_service,
depreciation_catch_up), so no write before consent leaves books P2 refuses
or misreads; replayed names are read with P2's TIN detector (B-28). The
cutover runs end to end through the real P2 and P3 binaries in a test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj

crates/ledger-cli/tests/fixtures/p2-served/blobs/69/7a/697a5b6d8f74f341972c78207e471c30d07ced60ef8a00827be79dadd9e8948b

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+%PDF-1.4 fictional receipt 17 Bank fee 3 2025-03-23