Add Ctrl+= / Ctrl+- / Ctrl+0 text size shortcuts

[x3m]

Browsers and terminals train the same reflex everywhere: Ctrl+= to grow the text, Ctrl+- to shrink it, Ctrl+0 to reset. Omawrite's editor size is fixed at 20px, so the only recourse today is the desktop-wide text scaling knob, which drags every other app along.

This wires that reflex up:

• Ctrl+= / Ctrl++ grows, Ctrl+- shrinks, Ctrl+0 resets to the current 20px default (clamped 8–72px).
• The size persists across sessions via the existing QSettings store ([layout] editorFontSize) — no new UI.
• The desktop text scale still multiplies on top exactly as before.
• The shortcuts are listed in the Ctrl+? dialog.

On current master the measure is a fixed 65 characters, so zooming changes glyph size at constant characters per line. Paired with #24 (editor fills the window by default), Ctrl+- also packs more characters per line, matching what the same shortcut does in a terminal. The PRs are independent; if both land, the two Settings blocks merge trivially.

Tested on Omarchy (Qt 6.11) with all three shortcuts, including persistence across restarts and the combination with #24.

🤖 Generated with Claude Code

https://claude.ai/code/session_01D5cK4VRT6nuLGuwEJrZvRD

[greptile-apps]

Greptile Summary

This follow-up adds persistent editor text-size shortcuts and completes the Qt compatibility fix by consistently requiring Qt 6.5 or newer.

• Adds Ctrl+=, Ctrl+-, and Ctrl+0 shortcuts with an 8–72px persisted editor font-size setting.
• Preserves desktop text scaling as a multiplier over the selected editor size.
• Enforces Qt 6.5+ in qmake configuration, Arch build/runtime dependencies, and documentation.
• Updates the keyboard-shortcut reference dialog.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
src/Main.qml	Adds persisted, bounded editor font sizing and application-wide zoom shortcuts while using the QtCore Settings type.
omawrite.pro	Rejects application builds using Qt versions older than the QML Settings requirement.
pkgbuild/PKGBUILD	Aligns Arch build-time and runtime Qt dependencies with the enforced Qt 6.5 minimum.
README.md	Documents the Qt 6.5 minimum required by the application.

_{Reviews (3): Last reviewed commit: "Add Ctrl+= / Ctrl+- / Ctrl+0 text size s..." | Re-trigger Greptile}

[greptile-apps]

QtCore Settings breaks older Qt

If Omawrite runs with Qt 6.0–6.4, import QtCore does not provide the new Settings type, so Main.qml fails to instantiate and the application exits before displaying a window. The project currently declares generic, unversioned Qt 6 requirements, so either retain the pre-6.5 settings import or raise the documented and packaged minimum to Qt 6.5.

Knowledge Base Used: Desktop application shell