Add follow button to feed item avatar (#3560)

* add follow button to feed item avatar

* remove confirmation

* add confirmation (just system alert)

* Shrink the avi follow indicator a smidge

* gate the follow button

* remove from your own posts

* add to post thread item

* hide the follow button locally to component

* Use native dropdown

* Add follow btn to notifications and search

* UI tweaks

* Hide on PWI

* Add toast for confirmation

* Check gate last

* compiler

* Rm unused

* Use names

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Co-authored-by: Paul Frazee <pfrazee@gmail.com>
Co-authored-by: Eric Bailey <git@esb.lol>
Co-authored-by: Dan Abramov <dan.abramov@gmail.com>

assets/icons/personPlus_stroke2_corner0_rounded.svg

@@ -0,0 +1 @@
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