Radial: suppress gesture while left button is held

An RMB press during a left-drag (mid-selection, or while setting up a
left+middle chord) must not pop the radial. Guard the gesture start on both
the tracked left-held-in-view flag and the live QMouseEvent::buttons() state
so a right press with left already down falls through instead of opening the
radial. All 5 ctest suites green.

docs/PLAN.md

@@ -137,6 +137,8 @@ Therefore the palette is replaced, not extended, and the replacement is built on
   does the usual primary-selection paste.
 - Right-button chords are intentionally **not** ported — the right button is the
   radial gesture. (Revisit later.)
+- The radial gesture is suppressed while the left button is held, so an RMB tap
+  mid-selection (or during a left+middle chord) does not pop the radial.
 
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 - `:`-verb pack via `KTextEditor::Command`: `sort`, `align`, `json`, `b64`,

src/plugin/ollieplugin.cpp

@@ -399,6 +399,13 @@ bool OllieView::eventFilter(QObject *obj, QEvent *event)
         return QObject::eventFilter(obj, event);
     }
 
+    // Suppress the radial when the left button is already held: the user is
+    // mid-selection (or setting up a left+middle chord), not starting a clean
+    // radial gesture. buttons() reports the other buttons down at press time.
+    if (m_leftDownInView || (me->buttons() & Qt::LeftButton)) {
+        return QObject::eventFilter(obj, event);
+    }
+
     // Pop the radial at the press position and begin the drag gesture. The
     // press is consumed so the context menu does not appear and the caret is
     // not moved (an intentional, configured trade-off).