P3: rename accounts, one set of period defaults, tax categories warn or refuse (defects 15, 16, 8)

books.rename_account; account names trimmed, bounded, refused when a
sibling's or TIN-shaped; books.show refuses what its target ignores. A
report asked for without dates covers this fiscal year so far, everywhere
(one rule for tools, descriptions and the viewer; the IIF and CPA package
keep their own dates). policy.require_tax_category warns or refuses; a
Form 4797 gain is shown apart on every return.

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

crates/ledger-gui/tests/old_books.rs

@@ -30,6 +30,7 @@ use chrono::NaiveDate;
 use egui_kittest::Harness;
 use ledger_gui::books::{Books, PartyPeriod};
 use ledger_gui::nav::{ReportKind, Route};
+use ledger_gui::pages::accounts::RegisterRange;
 use ledger_gui::pages::reports::{Columns, Compare, Range};
 use ledger_gui::{App, Source, data};
 use serde_json::json;
@@ -360,7 +361,7 @@ fn every_page_renders(shard: usize, of: usize) {
         for at in edges {
             h.state_mut().state_mut().assets.as_of = Some(at);
             show(&mut h, Route::Assets);
-            h.state_mut().state_mut().accounts.range = Some((NaiveDate::MIN, at));
+            h.state_mut().state_mut().accounts.range = RegisterRange::Dates(NaiveDate::MIN, at);
             for &a in &accounts {
                 show(&mut h, Route::Account(a));
             }