Two macOS reports: both were Qt deciding, so both differed by platform

Settings sat closer to its icon than Dashboard and Giám sát do. Those are tree
rows, laid out by the style; Settings was a QPushButton, whose icon-to-label gap
is also the style's — and the two do not agree. The Windows fix for this was a
19px icon box that nudged the label 1px, which is exactly the kind of tuning
that only holds on the machine it was measured on: on macOS the gap is tighter
again. The row now lays itself out, 4px in and 6px between, the same two numbers
the tree uses. Icon x=4 and label x=26 against the rows' 4 and 26 — equal, not
close.

The language drop-list showed a tick over its own text. macOS marks the current
row with a checkmark and Windows does not, and the popup inherits the combo's
width — which for "EN/JP/VN" is about 50px, all of it needed by the letters.
widen_popup() measures the longest item plus the platform's indicator and sets
the view's minimum, so the tick has its own room wherever it is drawn.

That check found two more: the project picker (191px of text in a 138px popup)
and the provider list (221px in 138px) were both truncating names here, tick or
no tick.

Neither could be reproduced on this machine, so the checks assert the property
that made the bug possible — spacing we control rather than the style's, and a
popup measured against text + indicator — not the platform.

21/21 checkers pass. check_nav segfaults in Qt teardown after printing its
verdict, twice in one suite run and 0 times in 8 standalone runs; pre-existing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

theme.py

@@ -498,11 +498,9 @@ QToolButton#navProjectPickMini::menu-indicator { image: none; width: 0; }
 
 QPushButton#navSettingsBtn {
     background: transparent; border: none; color: $text_muted;
-    padding: 6px 8px 6px 4px; text-align: left; border-radius: ${radius}px;
-    /* A button leaves less air between icon and label than a tree row
-       does, so the word sat 3px left of Dashboard's. Widening the icon
-       box (the glyph stays 16px, left-aligned) closes the gap. */
-    qproperty-iconSize: 19px 16px;
+    /* Padding stays at 0: the row lays its own icon and label out, so that
+       the spacing does not change with the platform's button style. */
+    padding: 0; text-align: left; border-radius: ${radius}px;
     /* No side margin: Settings reads as one more row under Dashboard/Giám sát,
        so its icon has to start on their x. A 6px margin put it at 14 — near
        enough the middle of the collapsed 54px rail to look centred. */