Use 1 pt steps for the text size slider

[NikKovIos]

Summary

The Text Size slider in Preferences only offered 8 sizes: 9, 10, 11, 12, 13, 14, 18 and 24 pt. Above 14 pt it jumped straight to 18 and then 24, so there was no way to pick an in-between size such as 16 pt.

This PR makes the slider offer every point size from 9 to 24 pt (16 tick marks).

Changes

• FontSizeTransformer.m — the size table now lists every size from 9 to 24 pt.
• PreferencesWindowController.xib — the slider has 16 tick marks (maxValue 15) and is 20 pt wider (186 → 206), so the denser tick marks stay easy to hit. The large "Aa" label still fits inside the window.

Compatibility

Existing values (9–14, 18 and 24 pt) map to the same sizes as before, so no one's setting changes after updating. Values set externally that aren't in the table keep the existing fallback behavior.

Testing

• Builds cleanly (Application scheme, Debug).
• In Preferences the slider shows 16 evenly spaced tick marks, and choosing an in-between tick writes the new size (for example, 16 pt) to GIUserDefaultKey_FontSize.

[greptile-apps]

Confidence Score: 5/5

[Medium risk] Changes text size slider granularity in preferences.

The PR appears safe to merge.

What we checked:

• Saved sizes stay unchanged: Saved settings hold point sizes. transformedValue: finds their new positions, and reverseTransformedValue: returns the same sizes.
• Wider slider still fits: The row fits within the 498-point window. The constraints retain a 10-point gap between the slider and the label.

Summary

The Text Size slider now offers every whole-point size from 9 to 24.

• Expands FontSizeTransformer to 16 sizes.
• Matches the slider’s range and tick count to the new table.
• Widens the slider by 20 points.
• Preserves existing saved sizes and fallback behavior.

No actionable issues found. Build and visual checks were not run; this macOS interface cannot run in the Linux review environment.

_{Reviews (1) · Last reviewed commit: "Use 1 pt steps for the text size slider" · Reviewed by Greptile}

[lucasderraugh]

Sounds good to me