[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/uuid.go

@@ -0,0 +1,27 @@
+package feeds
+
+// relevant bits from https://github.com/abneptis/GoUUID/blob/master/uuid.go
+
+import (
+	"crypto/rand"
+	"fmt"
+)
+
+type UUID [16]byte
+
+// create a new uuid v4
+func NewUUID() *UUID {
+	u := &UUID{}
+	_, err := rand.Read(u[:16])
+	if err != nil {
+		panic(err)
+	}
+
+	u[8] = (u[8] | 0x80) & 0xBf
+	u[6] = (u[6] | 0x40) & 0x4f
+	return u
+}
+
+func (u *UUID) String() string {
+	return fmt.Sprintf("%x-%x-%x-%x-%x", u[:4], u[4:6], u[6:8], u[8:10], u[10:])
+}