[feature] Add opt-in RSS feed for account's latest Public posts (#897)

* start adding rss functionality

* add gorilla/feeds dependency

* first bash at building rss feed
still needs work, this is an interim commit

* tidy up a bit

* add publicOnly option to GetAccountLastPosted

* implement rss endpoint

* fix test

* add initial user docs for rss

* update rss logo

* docs update

* add rssFeed to frontend

* feed -> feed.rss

* enableRSS

* increase rss logo size a lil bit

* add rss toggle

* move emojify to text package

* fiddle with rss feed formatting

* add Text field to test statuses

* move status to rss item to typeconverter

* update bun schema for enablerss

* simplify 304 checking

* assume account not rss

* update tests

* update swagger docs

* allow more characters in title, trim nicer

* update last posted to be more consistent

vendor/github.com/gorilla/feeds/AUTHORS

@@ -0,0 +1,29 @@
+# This is the official list of gorilla/feeds authors for copyright purposes.
+# Please keep the list sorted.
+
+Dmitry Chestnykh <dmitry@codingrobots.com>
+Eddie Scholtz <eascholtz@gmail.com>
+Gabriel Simmer <bladesimmer@gmail.com>
+Google LLC (https://opensource.google.com/)
+honky <honky@defendtheplanet.net>
+James Gregory <james@jagregory.com>
+Jason Hall <imjasonh@gmail.com>
+Jason Moiron <jmoiron@jmoiron.net>
+Kamil Kisiel <kamil@kamilkisiel.net>
+Kevin Stock <kevinstock@tantalic.com>
+Markus Zimmermann <markus.zimmermann@nethead.at>
+Matt Silverlock <matt@eatsleeprepeat.net>
+Matthew Dawson <matthew@mjdsystems.ca>
+Milan Aleksic <milanaleksic@gmail.com>
+Milan Aleksić <milanaleksic@gmail.com>
+nlimpid <jshuangzl@gmail.com>
+Paul Petring <paul@defendtheplanet.net>
+Sean Enck <enckse@users.noreply.github.com>
+Sue Spence <virtuallysue@gmail.com>
+Supermighty <ukiah@faction.com>
+Toru Fukui <fukuimone@gmail.com>
+Vabd <vabd@anon.acme>
+Volker <lists.volker@gmail.com>
+ZhiFeng Hu <hufeng1987@gmail.com>
+weberc2 <weberc2@gmail.com>
+