gui: Save PDF on every report; short and narrow windows hold up

Reports get a Save PDF button beside Copy for a spreadsheet. It typesets
the report as it's set up on screen (range, months/quarters/years,
comparison) through ledger-import's Typst statement template, the same
one the CPA package uses, in the background, writes it to the Downloads
folder (never the books: the viewer stays read-only), and opens it.

- ledger-import: Statement.percent_from marks percentage columns
  (comparison %, % of income), typeset as 12.5% with no dollar sign;
  wide statements turn the page, and past seven columns set smaller so
  a year of months fits; statement() is public for other callers.
- Compared columns that read the same (Jan 1 - Oct 12 vs a year
  earlier) now say which year, on screen and on paper.
- Short windows: the sidebar's and rail's links scroll above the status
  box instead of under it. The search palette fits the window.
- A test typesets every table-backed report from the demo books,
  plain, by month, and compared (PDF_DIR keeps the files).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX

crates/ledger-gui/Cargo.toml

@@ -14,6 +14,7 @@ path = "src/main.rs"
 ledger-core = { path = "../ledger-core" }
 ledger-store = { path = "../ledger-store" }
 ledger-config = { path = "../ledger-config" }
+ledger-import = { path = "../ledger-import" }
 eframe = { version = "0.36", default-features = false, features = ["default_fonts", "wgpu", "wayland", "x11", "persistence"] }
 egui = "0.36"
 egui_extras = { version = "0.36", features = ["image", "datepicker", "serde"] }