Refactor feed manipulation and rendering to be more robust (#297)

src/view/com/posts/FeedSlice.tsx

@@ -0,0 +1,28 @@
+import React from 'react'
+import {FeedSliceModel} from 'state/models/feed-view'
+import {FeedItem} from './FeedItem'
+
+export function FeedSlice({
+  slice,
+  showFollowBtn,
+  ignoreMuteFor,
+}: {
+  slice: FeedSliceModel
+  showFollowBtn?: boolean
+  ignoreMuteFor?: string
+}) {
+  return (
+    <>
+      {slice.items.map((item, i) => (
+        <FeedItem
+          key={item._reactKey}
+          item={item}
+          isThreadParent={slice.isThreadParentAt(i)}
+          isThreadChild={slice.isThreadChildAt(i)}
+          showFollowBtn={showFollowBtn}
+          ignoreMuteFor={ignoreMuteFor}
+        />
+      ))}
+    </>
+  )
+}