Shared parties with exact shares, member capital statements, TINs for any party, K-1 worksheet

Entries may name several parties, each with an exact amount, a percent,
or a share derived from the members' capital lines or [[company.members]]
shares (entry.parties_set); shares always sum exactly. The 1099
worksheet counts a vendor's share. A member's party page is their
partner capital statement, from the same ledger_core::k1 source as the
CPA package.

books.set_tin stores any party's TIN (members' SSNs for K-1s) in the
vault (party.tin_set, last four in the books). The CPA package carries a
K-1 member worksheet (k1-members.csv, with a members' total that ties to
Schedule L) and the 1099 worksheet with full TINs, saved outside the
books only. files_jointly_with notes spouses' two K-1s land on one 1040.

Adversarial review fixes: reversed contributions no longer inflate K-1
contributions and distributions; a K-1 row never takes another party's
TIN; TIN detection covers dot/slash/dash separators; refusals redact
TINs; vendor tagging can't silently replace shared parties; reversals
follow re-apportioning.

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

crates/ledger-mcp/tests/spec_mcp.rs

@@ -681,6 +681,10 @@ fn happy_path(name: &str) -> Mcp {
         "books.set_w4",
         json!({"party": "Pat", "received_on": "2026-01-02", "state": "UT", "kept_at": "binder"}),
     );
+    m.ok(
+        "books.set_tin",
+        json!({"party": "Pat", "tin": "291-12-2846", "tin_type": "ssn"}),
+    );
     m.ok(
         "books.set_party_roles",
         json!({"party": "Landlord", "add": ["landlord"]}),
@@ -1069,7 +1073,12 @@ fn happy_path(name: &str) -> Mcp {
     }
     m.ok(
         "books.export_cpa_package",
-        json!({"as_of": "2026-12-31", "include_receipts": false}),
+        json!({"as_of": "2026-12-31", "include_receipts": false, "include_tins": false}),
+    );
+    m.ok(
+        "books.export_cpa_package",
+        json!({"as_of": "2026-12-31", "include_receipts": false,
+               "save_to": outside(&dir).join("cpa.zip").to_str().unwrap()}),
     );
 
     m