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-mcp/tests/spec_vault.rs

@@ -2071,6 +2071,7 @@ fn idempotent_tools_change_nothing_when_repeated() {
         ("6300", "Insurance", "expense"),
     ]);
     m.add_party("Dana Employee", &["employee"]);
+    m.ok("books.add_project", json!({"name": "Harbor"}));
     let entry = m.post(
         "2026-02-01",
         json!({}),
@@ -2193,6 +2194,10 @@ fn idempotent_tools_change_nothing_when_repeated() {
             "books.set_fx_rate",
             json!({"currency": "EUR", "date": "2026-01-02", "rate": "1.10"}),
         ),
+        (
+            "books.update_project",
+            json!({"project": "Harbor", "kind": "client", "status": "paused"}),
+        ),
     ];
     let list = m.rpc("tools/list", json!({}));
     let marked: std::collections::BTreeSet<String> = list["result"]["tools"]