Call the record's boxes what they are

The offer names are from the protocol before this one, where a widget was
drawn twice and the record had to say which drawing was the question. It
is asked once now, so offer_part is the part it was asked in, offer_place
the place it was asked at, and place where its drawing was put: part,
asked and placed. LayoutHolds::frame is a range on the window since the
frame became a length of one, and the frame's own entry is the frame_len
pin beside it, so it is window; Painter::frame_own goes with it.
answers_at had one caller and said less than the line that replaces it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

core/src/ui/layout_holds.rs

@@ -20,7 +20,7 @@ const AXES: [Axis; 2] = [Axis::X, Axis::Y];
 /// whatever the frame turns out to be.
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub struct LayoutHolds {
-    pub frame: [Holds; 2],
+    pub window: [Holds; 2],
     pub frame_len: [Option<Len>; 2],
     pub extent: [Holds; 2],
     pub extent_len: [Option<Len>; 2],
@@ -28,7 +28,7 @@ pub struct LayoutHolds {
 
 impl LayoutHolds {
     pub const ANY: Self = Self {
-        frame: [Holds::ANY; 2],
+        window: [Holds::ANY; 2],
         frame_len: [None; 2],
         extent: [Holds::ANY; 2],
         extent_len: [None; 2],
@@ -37,7 +37,7 @@ impl LayoutHolds {
     pub fn and(self, other: Self) -> Self {
         let mut result = Self::ANY;
         for n in 0..2 {
-            result.frame[n] = self.frame[n].and(other.frame[n]);
+            result.window[n] = self.window[n].and(other.window[n]);
             result.extent[n] = self.extent[n].and(other.extent[n]);
             debug_assert!(
                 self.extent_len[n].is_none()
@@ -57,8 +57,8 @@ impl LayoutHolds {
 
     pub fn covers(self, other: Self) -> bool {
         (0..2).all(|n| {
-            self.frame[n].lo <= other.frame[n].lo
-                && self.frame[n].hi >= other.frame[n].hi
+            self.window[n].lo <= other.window[n].lo
+                && self.window[n].hi >= other.window[n].hi
                 && self.extent[n].lo <= other.extent[n].lo
                 && self.extent[n].hi >= other.extent[n].hi
                 && self.extent_len[n].is_none_or(|len| other.extent_len[n] == Some(len))
@@ -70,7 +70,7 @@ impl LayoutHolds {
         AXES.into_iter().all(|axis| {
             let n = axis as usize;
             let len = extent.axis(axis).len();
-            self.frame[n].contains(window.axis(axis))
+            self.window[n].contains(window.axis(axis))
                 && self.frame_len[n].is_none_or(|pinned| pinned == frame.axis(axis))
                 && self.extent[n].contains(len.to_px(window.axis(axis)))
                 && self.extent_len[n].is_none_or(|pinned| pinned == len)