feat: configurable page margins with printer-safe defaults (report-print)

[the-narwhal]

Problem
When opening the Report Print View for any financial report (General Ledger, Profit & Loss, Trial Balance, and Balance Sheet) and clicking Save as PDF or Print, the report content renders flush to the page edge. This causes two issues:

• The output looks visually unprofessional with no breathing room around the content
• Most laser and inkjet printers have a hardware-enforced minimum unprintable zone (~0.4–1.2 cm), so content near the edge is physically clipped when sent to a printer

Solution

A Page Margins section has been added to the existing right-hand configuration pane in the Report Print View. It sits between the Size Selection and Pick Columns sections.

Controls

• Four Float inputs — Top, Bottom, Left, Right — each accepting 0–5 cm with decimal precision
• A "Use Recommended" button that sets all four sides to 1.5 cm in one click
• A hint line explaining the recommended value: "1.5 cm (~0.6 in) per side is a safe default for most printers."

Default behaviour
Margins initialise to 1.5 cm on all sides. This was chosen because:

Printer type	Typical hardware minimum
Laser (HP, Canon, Brother, Xerox)	~0.4 cm (0.17 in)
Inkjet	0.3–1.2 cm
General safe zone	≤ 0.6 cm

1.5 cm comfortably clears every printer's minimum and matches the default margins used by word processors such as Microsoft Word and Google Docs.

Why no backend changes were needed
The margins are applied as an inline CSS padding on the content container div inside ScaledContainer. Because inline style attributes have higher CSS specificity than the * { padding: 0 } rule in the print stylesheet, the padding survives the print render unchanged. The padded HTML is embedded directly in the content string passed through constructPrintDocument, so both printToPDF (Save as PDF) and the native print dialog path pick it up automatically. The existing @page { margin: 0 } contract in the print CSS is preserved.

Files changed

File	Change
src/pages/PrintView/ReportPrintView.vue	Added Float import, margins data, contentPaddingStyle computed, setRecommendedMargins method, margin UI section in settings pane

Testing

1. Open any report (General Ledger, Profit & Loss, Balance Sheet, etc.)
2. Click the printer icon → Report Print View opens
3. Confirm the preview shows 1.5 cm inset content by default
4. Adjust Top/Bottom/Left/Right inputs — preview updates live
5. Click "Use Recommended" — all four inputs reset to 1.5
6. Click Save as PDF — open the PDF and confirm margins are applied
7. Click Print — send to a physical printer and confirm content is not clipped

Example of new margin configuration set to 0:

Example of new margin configuration set to 1.5: