Port the sketch usability fixes: Enter/Esc, rename, stale picks

Carries snaporca 95e59289f9, faec177d42 and 20df726ecb. Parity re-verified: 17 files identical,
8 diverging by their expected counts — DesignCanvas.cpp back to 16 and DesignPanel.cpp back to
32, which is the proof each hunk landed on the right side of the FeatFlyout and TAB_ID_PREPARE
divergences rather than on top of them.

All three answer exussum12's review on OrcaSlicer PR #15238.

ENTER/ESC IN THE VALUE FIELD. The field is a borderless always-on-top frame, and whether it may
hold keyboard focus is the platform's decision — a borderless NSWindow can never be key, and
mutter refuses a re-mapped window. When focus is denied the keys reach the panel instead and the
queued-dimension chain (a line queues Length then Angle) cannot be walked. The CHAR_HOOK now
forwards Enter/Numpad-Enter/Tab/Esc to the field when it is open and unfocused, and stays out of
the way when it is focused.

ESC FROM ANYWHERE. Separately and more simply: `dismissable` is false throughout sketch mode
because m_active is the FEATURE tool, so Esc fell through to whatever widget had focus. Click
any toolbar button or the Construction checkbox first and Esc did nothing at all — the likelier
reading of "Esc hardly ever works", and platform-independent. DesignCanvas exposes
request_sketch_exit() and the hook calls it whenever a sketch is live, after the inline-field
forwarding so an open field still takes Esc first.

RENAME. wxTR_EDIT_LABELS plus the two label-edit events write through to CadFeature::name and the
recipe, with a Rename verb in the offer and F2. The rebuild is deferred with CallAfter because
refresh_tree() destroys the very wxTreeItemId wx is holding during END_LABEL_EDIT — inline, it
killed the process.

STALE PICKS. set_tool now drops the Dimension tool's first pick, the Constrain picks and
m_point_sel, and delete_selected clears the pending dimension reference that could otherwise
dereference a renumbered entity.

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

src/slic3r/GUI/CAD/DesignSketchTool.cpp

@@ -241,6 +241,15 @@ void DesignSketchTool::set_tool(Mode mode)
     // the value away and reverted the corner to sharp, with nothing on screen saying so.
     reset_op();                 // drop any in-progress (not yet ready) edit-op gizmo
     reset_tf();                 // drop any in-progress transform gizmo
+    // A pick that survives the tool that made it is invisible, and the first sign of it is a
+    // constraint or a dimension landing on geometry the user did not choose. Drop the modal
+    // picks left armed by the tool we are leaving: the Dimension tool's first pick, the
+    // Constrain tool's picks, and the individual point selection.
+    m_dim_has0 = false;
+    m_dim_e0   = -1;
+    m_dim_r0   = SketchPointRole::P0;
+    m_pick0 = m_pick1 = m_pick2 = -1;
+    m_point_sel.clear();
     m_selection.clear();
     if (on_selection_changed) on_selection_changed(0);
 }
@@ -328,6 +337,11 @@ void DesignSketchTool::delete_selected()
     m_dimensions.clear();
     m_dim_has0 = false;
     m_pending_dim = -1;
+    // The Dimension tool's pending FIRST pick is the same dangling-reference hazard as the placed
+    // quotes just cleared above: it references an entity index that has shifted or gone away, and
+    // a stale m_dim_e0 would dereference out of range on the next click. Drop it too.
+    m_dim_e0 = -1;
+    m_dim_r0 = SketchPointRole::P0;
     if (on_selection_changed) on_selection_changed(0);
 }