feat: primitive pointer modifiers, type chooser fixes, double-click to edit

Type chooser:
- Fix PointerTarget mode hiding primitives due to stale modifier state
- Preselect */[n] modifier buttons to reflect current node type
- Primitive pointer support: int32*, double**, etc with provider deref
- hex64*/ptr64* with * modifier falls back to void* (meaningless deref)
- isValidPrimitivePtrTarget guard in controller, compose, format
- Modifier toggle no longer resets list selection
- Primitive pointers open FieldType mode (not PointerTarget)
- Type edit requires double-click (was single-click, too easy to misclick)

Other:
- Custom dock titlebar with themed close button, no float button
- Status bar font synced at startup
- Resize grip reworked as direct MainWindow child, font-independent
- File menu "Source" renamed to "Current Tab Source"

Tests: 41 type_selector, 39 editor, 17 controller (200 total, 0 failures)

src/editor.cpp

@@ -1789,15 +1789,7 @@ bool RcxEditor::eventFilter(QObject* obj, QEvent* event) {
                 // Single-click on editable token of already-selected node → edit
                 int tLine, tCol; EditTarget t;
                 if (hitTestTarget(m_sci, m_meta, me->pos(), tLine, tCol, t)) {
-                    // Type/ArrayElementType/PointerTarget open a dismissible popup
-                    // (not inline text edit), so allow on first click without
-                    // requiring the node to be pre-selected.
-                    bool isPopupTarget = (t == EditTarget::Type
-                                       || t == EditTarget::ArrayElementType
-                                       || t == EditTarget::PointerTarget);
-                    if ((alreadySelected || isPopupTarget) && plain) {
-                        if (!alreadySelected)
-                            emit nodeClicked(h.line, h.nodeId, me->modifiers());
+                    if (alreadySelected && plain) {
                         m_pendingClickNodeId = 0;
                         return beginInlineEdit(t, tLine, tCol);
                     }