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-mcp/src/scopes.rs

@@ -62,7 +62,7 @@ const C: Needs = PostWhenConfirmed;
 const K: Needs = PostForApprovalRules;
 
 /// Every tool and what it needs (INVARIANT 1).
-pub const TABLE: [(&str, Needs); 111] = [
+pub const TABLE: [(&str, Needs); 112] = [
     ("books.handbook", R),
     ("books.start", R),
     // Settings are committed at once: the settings commit of the plan.
@@ -123,6 +123,7 @@ pub const TABLE: [(&str, Needs); 111] = [
     ("books.chart_template", R),
     ("books.tax_categories", R),
     ("books.renumber_account", P),
+    ("books.rename_account", P),
     ("books.label_asset", W),
     ("books.correct_asset", P),
     ("books.set_asset_tax_basis", W),