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/active.rs

@@ -19,17 +19,17 @@ pub struct ActiveData {
     /// forwards the parent's frame. What it declared is kept separately in
     /// `declared` and is a fraction of whichever of the two reached it.
     pub narrow: [Option<Len>; 2],
-    /// Where its drawing was put, as a part of its parent's box, and where
-    /// it was asked. The two differ where a container asks in one place and
-    /// places the answer in another -- a row measures from its cursor and
+    /// Where its drawing was put, and where it was asked, each as a part of
+    /// its parent's box. The two differ where a container asks in one place
+    /// and puts the answer in another -- a row measures from its cursor and
     /// puts the child in its slot. A part is a length from the box's start,
     /// so a box that moved re-places every child by re-adding that start.
-    pub place: [Place; 2],
-    pub offer_place: [Place; 2],
+    pub placed: [Place; 2],
+    pub asked: [Place; 2],
     /// The box it was asked in, in the parent's region-node coordinates: the
     /// box its drawing was made in and the one its contract is about. Its
     /// drawing is placed elsewhere by re-expression, never by asking again.
-    pub offer_part: UiRegion,
+    pub part: UiRegion,
     /// The measured answer and its dependencies. A hint-only dependency or
     /// a widget first encountered during placement has no measurement yet.
     pub answer: Option<(Size, LayoutHolds)>,
@@ -82,20 +82,10 @@ pub struct ActiveData {
 }
 
 impl ActiveData {
-    /// What it answered when its parent measured it, where it has been
-    /// measured at all. Not `size`, which is what its last drawing reported:
-    /// a drawing made in the box that answer chose is answering a different
-    /// question.
+    /// What it answered when its parent asked, where it has been asked at
+    /// all. Not `size`, which is what its last drawing reported: a drawing
+    /// re-expressed in the box that answer chose is not a second answer.
     pub fn measured(&self) -> Option<Size> {
         self.answer.map(|(size, _)| size)
     }
-
-    /// Whether what it answered still stands in this window, for the frame
-    /// and the box it was asked in. The answer was given in the box its
-    /// parent first asked about, which is what it is checked against --
-    /// `holds` on the record is about the box the answer then chose.
-    pub fn answers_at(&self, window: crate::PxVec2, part: UiRegion) -> bool {
-        self.answer
-            .is_some_and(|(_, holds)| holds.contains(window, self.frame, part))
-    }
 }