merge: P6, the evidence pipeline (branch P6, checkpoint ce366408)

The last of the paused branches, from its "not for merge" checkpoint:
extraction in ledger-import (text, pages, page images; capped, caught),
journaled as attachment.text_extracted; dedup by hash with
books.find_attachment and books.consolidate_duplicates; annotations and
books.set_entry_settles; the company record categories; the two fuzz
targets; feature attachment_text. Nineteen files conflicted with the
four P4b merges, resolved as plan 8.0.2 says: P6 retakes schema 18 (it
had taken 16, which S4.3 holds; S5 holds 17); the tool table is 129 and
the destructive count 31; both sides' appends kept with their seams
restored; one B-27 paragraph naming every feature; in the old-books
fixture P6's hand-written reimbursement is entry 7 (its ids collided
with S4.3's invoice); the replay fuzzer's list gains S7's
invoice.written_off; S4.3's issued-PDF test expects the extraction
record P6 journals right after a filing.

One integration defect between S7 and P6, found by the arap property
test and fixed here: under P6's dedup, a write-off whose evidence bytes
were filed already (the same collection letter for a second write-off of
the same invoice) was refused only after its entry had been journaled,
at the final link to the invoice ("already linked"). The write-off now
resolves the dedup before anything is journaled and keeps a link the
record already has to the invoice instead of refusing it; an explicit
existing_attachment_id already on an entry is still refused (S7's
one-receipt-once rule). P6's gate never ran before the pause; it runs on
main after this merge, and its ledger-store -> ledger-import dependency
is the open review point (plan 8.0.1).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp

crates/ledger-core/src/lib.rs

@@ -25,6 +25,7 @@ pub mod cashflow;
 pub mod classes;
 pub mod conventions;
 pub mod error;
+pub mod evidence;
 pub mod form1099;
 pub mod instruments;
 pub mod journal;
@@ -69,6 +70,7 @@ pub use cashflow::{
 };
 pub use classes::{Class, ClassId, ProjectFacts, ProjectKind, ProjectStatus};
 pub use error::LedgerError;
+pub use evidence::{Annotation, AnnotationFields};
 pub use form1099::{
     Dated1099, Decision1099, ExemptReason, Form1099, Payment1099, PaymentAccounts, Status1099,
     Vendor1099Line, Vendor1099Report, vendor_1099_report,