Reduce the minimum main-window size

[thsnkhn]

Problem

A MacBook user reported that the Harbor window remains too large even after it is resized to its current minimum dimensions.

Goal

Allow Harbor to fit comfortably on smaller laptop screens while keeping the primary controls usable.

Acceptance criteria

• Reduce the minimum width and height of the main window.
• The downloads list remains usable at the new minimum size.
• Sidebars and the inspector collapse, resize, or scroll without clipping controls.
• Toolbar actions remain reachable.
• Sheets fit within the available screen.
• Restored window dimensions are clamped to the current display.
• Verify the layout on a small MacBook-sized display.

Source

Reported in the Harbor 1.7.0 Reddit announcement.