P3: assets' posted and scheduled depreciation, their bases, and the K-1 on the tax basis (defect 13, D-41)

Book value is cost less what the books posted; the schedule's figure is
apart. An asset's acquired date comes from its entry. Contributed
property keeps its section 723 carryover basis apart from its depreciable
basis (the lower of value and adjusted basis), with its 704(c) built-in
gain and method. The K-1 worksheet reports tax-basis capital (Form 1065
Item L) beside the book figures, leaving open what only the CPA knows.

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

crates/ledger-core/src/k1.rs

@@ -169,17 +169,9 @@ pub fn k1_detail(
     }
     let me = members_equity(ledger, start, end, members)?;
     let places = ledger.base_currency().allocation_places();
-    let receivables = ledger.role_account(&crate::RECEIVABLES);
     let closings = ledger.closing_entry_ids();
     let cancelled = crate::reports::cancelled_in_span(ledger, start, end);
-    let property_account = |id: AccountId| {
-        !cash.contains(&id)
-            && Some(id) != receivables
-            && ledger
-                .chart()
-                .get(id)
-                .is_some_and(|a| a.account_type == AccountType::Asset)
-    };
+    let property_account = |id: AccountId| is_property_account(ledger, cash, id);
     let sum = |e: &crate::JournalEntry, side: Side, account: AccountId| -> Decimal {
         e.lines()
             .iter()
@@ -274,6 +266,18 @@ pub fn k1_detail(
     Ok(K1Detail { rows, lines })
 }
 
+/// Whether an account holds property (INVARIANT 3): an asset account that
+/// is neither cash (`cash`) nor receivables. The tax-basis capital
+/// worksheet (crate::tax_capital) reads property the same way.
+pub(crate) fn is_property_account(ledger: &Ledger, cash: &[AccountId], id: AccountId) -> bool {
+    !cash.contains(&id)
+        && Some(id) != ledger.role_account(&crate::RECEIVABLES)
+        && ledger
+            .chart()
+            .get(id)
+            .is_some_and(|a| a.account_type == AccountType::Asset)
+}
+
 /// One entry's property shared among the members' credits in it
 /// (INVARIANT 4): at most their total credit, in proportion to each
 /// credit, rounded toward zero to `places` (the base currency's