Adds a composer prompt on the home screen to invite users to post (#9464)

* Add a composer prompt on home

* Added image upload button

* Feed composer buttons

* Feed composer styles

* Add client events, auto-open gallery when button is pressed

* Add feature gate

* Move gate check to last

* Small style cleanups

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Co-authored-by: Eric Bailey <git@esb.lol>

src/view/shell/Composer.ios.tsx

@@ -45,6 +45,7 @@ export function Composer({}: {winHeight: number}) {
             text={state?.text}
             imageUris={state?.imageUris}
             videoUri={state?.videoUri}
+            openGallery={state?.openGallery}
           />
         </TooltipSheetCompatProvider>
       </View>