Quick terminal: make the panel size configurable (the 1100x700 cap is small on a large 4k display)

[SmetDenis]

What I'm trying to do

Use the quick terminal to glance at output while an agent works in a session behind it — git diff, a build log, the tail of a file it just wrote. Summoned by the global hotkey over whatever is in front, read, dismissed. The detached panel from #441 is exactly the right primitive: non-activating, dismiss-on-blur, shell alive across hides.

The gap

The frame is fixed in QuickTerminal.targetFrame():

private static let maxNormalSize = NSSize(width: 1100, height: 700)

let size = NSSize(width:  min(visible.width  * 0.9, maxNormalSize.width),
                  height: min(visible.height * 0.9, maxNormalSize.height))

Past roughly 1220x780 points the 90% share never applies — the cap always wins. On my 32" 4K display (HiDPI, 2560x1440 points) that is 43% of the width and 49% of the height, so the panel covers about 21% of the screen area where the 90%/90% shape intends 81%. Reading a wide git diff in it means scrolling sideways with the space to avoid that sitting empty around it. On the built-in Retina panel the same cap lands near the intended share and feels right — which is the point: the cap is a good default that ages badly with screen size.

I am not asking to change that default. #441 is right that 90% of a large display is "a wall of terminal". I am asking for a way to move the tradeoff.

What would help

One key, defaulting to today's behavior:

• a percentage — quick-terminal-size = 70% in the agterm-scoped ghostty.conf (or width/height in Settings), replacing the 90%/cap pair; or
• a cap override — keep the 90% share, configure only the ceiling: quick-terminal-max-size = 1600x1000.

What I tried instead

• surface zoom show --target quick — readable, but hide() clears isZoomed, so every summon is 1100x700 again. And it only offers the two extremes: the cap or the full screen the cap exists to avoid.
• A custom keymap.conf command (quick show + surface zoom) — works only while agterm is frontmost, and global-hotkey is bound to the quick terminal itself, so it cannot stand in for the summon.
• quick-terminal-size in the agterm-scoped ghostty.conf — parsed by libghostty and silently ignored, since agterm computes the frame itself. Might deserve a docs note on its own.
• Dragging the panel edge — it is a .borderless NSPanel, so there is no edge, and it is re-framed on every show anyway.

Environment

agterm 0.24.0, macOS 26.2, Apple Silicon. External 32" 4K display at 2560x1440 points (main) plus the built-in Retina panel.

[umputun]

done, merged in #459 and it will be in the next release.

Settings ▸ Interface ▸ Quick Terminal ▸ Size, offering Default plus 40% to 90% in tens. Unset reproduces the current frame exactly, so nothing changes for anyone who does not touch it.

I took the percentage rather than the quick-terminal-max-size cap override you offered as the alternative. A ceiling in points is what ages badly across displays in the first place, so making that ceiling configurable moves the same problem to the next screen size instead of removing it. A set percentage drops both the 90% share and the 1100x700 pair and takes that share of whatever screen the panel opens on. 90 is the top of the range because that is the share the original design documented, and filling the screen already has its own meaning through surface zoom.

Your reading of the code was right on every point, including hide() clearing isZoomed, which is why the zoom workaround did not survive a summon, and the panel being borderless so there is no edge to drag. One thing from your report is not in this PR: the scoped ghostty.conf quick-terminal-size key is still parsed by libghostty and still ignored, with nothing in the docs saying so.