Projects: classes as entities, and the sidebar fits short windows

A project is a class with facts (description, status, kind, party,
dates, links, notes) in one project.set event behind the format
feature projects. Four tools (books.add_project, update_project,
projects, project); documents and decisions link to projects; B-37:
on-spec costs are expensed as incurred, repayment is revenue, and the
unrecovered cost is never below zero (Kani). Viewer: a Projects list
and a project page with its figures, by month and by account. The
sidebar measures its footer instead of reserving a fixed 172 px.

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

crates/ledger-gui/src/pages/cash.rs

@@ -135,6 +135,7 @@ pub fn show(ui: &mut Ui, b: &Books, shell: &mut Shell<'_>) {
                             .map(|(s, _, i, o)| BarGroup {
                                 label: s.format("%b").to_string(),
                                 values: vec![*i, *o],
+                                year: None,
                             })
                             .collect();
                         charts::bar_chart(