Rename companion field to CompanionInstance instead of nested type

Switch approach: rename the static peer field rather than the nested companion type. Consumers now write e.g. `Color.CompanionInstance.Red` (instead of `Color.Companion.Red`), keeping the nested type name as the more accurate `<Outer>.Companion` that mirrors the Kotlin/Java source.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: jonathanpeppers

source/androidx.compose.foundation/foundation-android/PublicAPI/PublicAPI.Unshipped.txt

@@ -73,18 +73,19 @@
   <attr path="/api/package[@name='androidx.compose.foundation']/class[@name='MutationInterruptedException']" name="visibility">public</attr>
 
   <!--
-    Kotlin `object` companion on a `class`: the nested peer binds as
-    `<Outer>.Companion`, which collides with the static `Companion` property the
-    generator would otherwise emit on the outer class (a nested type and a
-    property can't share a name), so the field is silently dropped and the
-    singleton is only reachable via raw JNI. Rename every nested `*.Companion`
-    peer to `CompanionStatic` (the same wildcard pattern kotlin-stdlib, okio,
-    aicore, and genai-prompt already use) so the generator surfaces
-    `public static <Outer>.CompanionStatic Companion { get; }` on every outer
-    class, letting consumers write e.g. `KeyboardOptions.Companion.Default`,
-    `ScrollState.Companion.Saver`, `LazyListState.Companion.Saver` directly.
-    (Interface companions are hoisted to top-level `<Outer>Companion` by the
-    generator before this rename matches, so they're unaffected.)
+    Kotlin `object` companion on a `class`: the JVM emits a `public static
+    Companion Companion;` field on the outer class plus a nested
+    `<Outer>.Companion` peer type. C# can't have both a static member and a
+    nested type with the same name, so the generator silently drops the static
+    field and the singleton is only reachable via raw JNI. Rename the static
+    field to `CompanionInstance` (leaving the nested type as
+    `<Outer>.Companion`) so the generator emits
+    `public static <Outer>.Companion CompanionInstance { get; }` on every outer
+    class — `KeyboardOptions.CompanionInstance.Default`,
+    `ScrollState.CompanionInstance.Saver`, `LazyListState.CompanionInstance.Saver`
+    are now reachable directly. Interface companions are unaffected — the
+    generator hoists their peer to top-level `<Outer>Companion` and emits a
+    public `CompanionStatic` accessor that this rename doesn't match.
   -->
-  <attr path="/api/package/class[substring(@name,string-length(@name)-9)='.Companion']" name="managedName">CompanionStatic</attr>
+  <attr path="/api/package/class/field[@name='Companion' and substring(@type,string-length(@type)-9)='.Companion']" name="managedName">CompanionInstance</attr>
 </metadata>